diff --git a/internal/imagedefinition/README.rst b/internal/imagedefinition/README.rst
index 8a7d2d88..1f53693e 100644
--- a/internal/imagedefinition/README.rst
+++ b/internal/imagedefinition/README.rst
@@ -111,6 +111,13 @@ The following specification defines what is supported in the YAML:
              # An alternative branch to use while retrieving seeds
              # from a git or bzr source.
              branch: <string> (optional)
+          # Whether to write the sources list as Deb822 formatted entries in 
+          # /etc/apt/sources.list.d/ubuntu.sources or not (and thus use the legacy format
+          # in /etc/apt/sources.list)
+          # Default to "false" for now to not break existing builds but a warning will be
+          # displayed and this default will switch at some point in the future.
+          # A warning is also displayed if no value was explicitely set for this field.
+          sources-list-deb822: <boolean> (optional)
          # Used for pre-built root filesystems rather than germinating
          # from a seed or using a list of archive-tasks. Must be an
          # an uncompressed tar archive or a tar archive with one of the
diff --git a/internal/imagedefinition/image_definition.go b/internal/imagedefinition/image_definition.go
index 7ea65659..8f708422 100644
--- a/internal/imagedefinition/image_definition.go
+++ b/internal/imagedefinition/image_definition.go
@@ -39,14 +39,15 @@ type Gadget struct {
 
 // Rootfs defines the rootfs section of the image definition file
 type Rootfs struct {
-	Components   []string `yaml:"components"    json:"Components,omitempty"   default:"main,restricted"`
-	Archive      string   `yaml:"archive"       json:"Archive"                default:"ubuntu"`
-	Flavor       string   `yaml:"flavor"        json:"Flavor"                 default:"ubuntu"`
-	Mirror       string   `yaml:"mirror"        json:"Mirror"                 default:"http://archive.ubuntu.com/ubuntu/"`
-	Pocket       string   `yaml:"pocket"        json:"Pocket"                 jsonschema:"enum=release,enum=Release,enum=updates,enum=Updates,enum=security,enum=Security,enum=proposed,enum=Proposed" default:"release"`
-	Seed         *Seed    `yaml:"seed"          json:"Seed,omitempty"         jsonschema:"oneof_required=Seed"`
-	Tarball      *Tarball `yaml:"tarball"       json:"Tarball,omitempty"      jsonschema:"oneof_required=Tarball"`
-	ArchiveTasks []string `yaml:"archive-tasks" json:"ArchiveTasks,omitempty" jsonschema:"oneof_required=ArchiveTasks"`
+	Components        []string `yaml:"components"    json:"Components,omitempty"   default:"main,restricted"`
+	Archive           string   `yaml:"archive"       json:"Archive"                default:"ubuntu"`
+	Flavor            string   `yaml:"flavor"        json:"Flavor"                 default:"ubuntu"`
+	Mirror            string   `yaml:"mirror"        json:"Mirror"                 default:"http://archive.ubuntu.com/ubuntu/"`
+	Pocket            string   `yaml:"pocket"        json:"Pocket"                 jsonschema:"enum=release,enum=Release,enum=updates,enum=Updates,enum=security,enum=Security,enum=proposed,enum=Proposed" default:"release"`
+	Seed              *Seed    `yaml:"seed"          json:"Seed,omitempty"         jsonschema:"oneof_required=Seed"`
+	Tarball           *Tarball `yaml:"tarball"       json:"Tarball,omitempty"      jsonschema:"oneof_required=Tarball"`
+	ArchiveTasks      []string `yaml:"archive-tasks" json:"ArchiveTasks,omitempty" jsonschema:"oneof_required=ArchiveTasks"`
+	SourcesListDeb822 *bool    `yaml:"sources-list-deb822" json:"SourcesListDeb822" default:"false"`
 }
 
 // Seed defines the seed section of rootfs, which is used to
@@ -307,57 +308,184 @@ type DependentKeyError struct {
 	gojsonschema.ResultErrorFields
 }
 
-func (imageDef ImageDefinition) securityMirror() string {
-	if imageDef.Architecture == "amd64" || imageDef.Architecture == "i386" {
+func (i ImageDefinition) securityMirror() string {
+	if i.Architecture == "amd64" || i.Architecture == "i386" {
 		return "http://security.ubuntu.com/ubuntu/"
 	}
-	return imageDef.Rootfs.Mirror
+	return i.Rootfs.Mirror
 }
 
-func generatePocketList(series string, components []string, mirror string, securityMirror string, pocket string) []string {
-	baseList := fmt.Sprintf("deb %%s %s%%s %s\n", series, strings.Join(components, " "))
+// generateLegacySourcesList returns the content to write to the sources.list file
+// under the legacy format.
+func generateLegacySourcesList(series string, components []string, mirror string, securityMirror string, pocket string) string {
+	baseList := fmt.Sprintf("deb %%s %s%%s %s", series, strings.Join(components, " "))
 
-	releaseList := fmt.Sprintf(baseList, mirror, "")
-	securityList := fmt.Sprintf(baseList, securityMirror, "-security")
-	updatesList := fmt.Sprintf(baseList, mirror, "-updates")
-	proposedList := fmt.Sprintf(baseList, mirror, "-proposed")
+	releaseSourceComment := `# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
+# newer versions of the distribution.
+`
+	updatesSourceComment := `## Major bug fix updates produced after the final release of the
+## distribution.
+`
 
-	pocketList := make([]string, 0)
+	releaseSource := releaseSourceComment + fmt.Sprintf(baseList, mirror, "")
+	securitySource := fmt.Sprintf(baseList, securityMirror, "-security")
+	updatesSource := updatesSourceComment + fmt.Sprintf(baseList, mirror, "-updates")
+	proposedSource := fmt.Sprintf(baseList, mirror, "-proposed")
+
+	sourcesList := make([]string, 0)
 
 	switch pocket {
 	case "release":
-		pocketList = append(pocketList, releaseList)
+		sourcesList = append(sourcesList, releaseSource)
 	case "security":
-		pocketList = append(pocketList, releaseList, securityList)
+		sourcesList = append(sourcesList, releaseSource, securitySource)
 	case "updates":
-		pocketList = append(pocketList, releaseList, securityList, updatesList)
+		sourcesList = append(sourcesList, releaseSource, securitySource, updatesSource)
+	case "proposed":
+		sourcesList = append(sourcesList, releaseSource, securitySource, updatesSource, proposedSource)
+	}
+
+	return strings.Join(sourcesList, "\n") + "\n"
+}
+
+// LegacyBuildSourcesList returns the content of the /etc/apt/sources.list to be used
+// during the build process
+func (i *ImageDefinition) LegacyBuildSourcesList() string {
+	return i.legacySourcesList(false)
+}
+
+// LegacyTargetSourcesList returns the content of the /etc/apt/sources.list for the target
+// image
+func (i *ImageDefinition) LegacyTargetSourcesList() string {
+	return i.legacySourcesList(true)
+}
+
+// legacySourcesList returns the content of the /etc/apt/sources.list file in the
+// legacy format (not deb822).
+func (i *ImageDefinition) legacySourcesList(target bool) string {
+	pocket := i.Rootfs.Pocket
+	if target {
+		pocket = i.Customization.Pocket
+	}
+
+	return generateLegacySourcesList(
+		i.Series,
+		i.Customization.Components,
+		i.Rootfs.Mirror,
+		i.securityMirror(),
+		strings.ToLower(pocket))
+}
+
+// generateDeb822Section returns a deb822 section/paragraph to be used in a sources list file
+// This function is tailored to what is expected in an official ubuntu image and should not be
+// used as is to generate arbitrary deb822 sections.
+func generateDeb822Section(mirror string, series string, components []string, pocket string) string {
+	sectionTmpl := `Types: deb
+URIs: %s
+Suites: %s
+Components: %s
+Signed-By: /usr/share/keyrings/ubuntu-archive-keyring.gpg
+
+`
+
+	suites := make([]string, 0)
+
+	switch pocket {
+	case "security":
+		suites = []string{series + "-security"}
 	case "proposed":
-		pocketList = append(pocketList, releaseList, securityList, updatesList, proposedList)
+		suites = append([]string{series + "-proposed"}, suites...)
+		fallthrough
+	case "updates":
+		suites = append([]string{series + "-updates"}, suites...)
+		fallthrough
+	case "release":
+		suites = append([]string{series}, suites...)
 	}
 
-	return pocketList
-}
-
-// BuildPocketList returns a slice of strings that need to be added to
-// /etc/apt/sources.list in the chroot to build the image, based on the value of "pocket"
-// in the rootfs section of the image definition
-func (imageDef ImageDefinition) BuildPocketList() []string {
-	return generatePocketList(
-		imageDef.Series,
-		imageDef.Rootfs.Components,
-		imageDef.Rootfs.Mirror,
-		imageDef.securityMirror(),
-		strings.ToLower(imageDef.Rootfs.Pocket))
-}
-
-// TargetPocketList returns a slice of strings that need to be added to
-// /etc/apt/sources.list in the chroot for the target image, based on the value of "pocket"
-// in the customization section of the image definition
-func (imageDef ImageDefinition) TargetPocketList() []string {
-	return generatePocketList(
-		imageDef.Series,
-		imageDef.Customization.Components,
-		imageDef.Rootfs.Mirror,
-		imageDef.securityMirror(),
-		strings.ToLower(imageDef.Customization.Pocket))
+	return fmt.Sprintf(sectionTmpl,
+		mirror,
+		strings.Join(suites, " "),
+		strings.Join(components, " "),
+	)
+}
+
+var LegacySourcesListComment = `# Ubuntu sources have moved to the /etc/apt/sources.list.d/ubuntu.sources
+# file, which uses the deb822 format. Use deb822-formatted .sources files
+# to manage package sources in the /etc/apt/sources.list.d/ directory.
+# See the sources.list(5) manual page for details.
+`
+
+var ubuntuSourceHeader = `## Ubuntu distribution repository
+##
+## The following settings can be adjusted to configure which packages to use from Ubuntu.
+## Mirror your choices (except for URIs and Suites) in the security section below to
+## ensure timely security updates.
+##
+## Types: Append deb-src to enable the fetching of source package.
+## URIs: A URL to the repository (you may add multiple URLs)
+## Suites: The following additional suites can be configured
+##   <name>-updates   - Major bug fix updates produced after the final release of the
+##                      distribution.
+##   <name>-backports - software from this repository may not have been tested as
+##                      extensively as that contained in the main release, although it includes
+##                      newer versions of some applications which may provide useful features.
+##                      Also, please note that software in backports WILL NOT receive any review
+##                      or updates from the Ubuntu security team.
+## Components: Aside from main, the following components can be added to the list
+##   restricted  - Software that may not be under a free license, or protected by patents.
+##   universe    - Community maintained packages.
+##                 Software from this repository is only maintained and supported by Canonical
+##                 for machines with Ubuntu Pro subscriptions. Without Ubuntu Pro, the Ubuntu
+##                 community provides best-effort security maintenance.
+##   multiverse  - Community maintained of restricted. Software from this repository is
+##                 ENTIRELY UNSUPPORTED by the Ubuntu team, and may not be under a free
+##                 licence. Please satisfy yourself as to your rights to use the software.
+##                 Also, please note that software in multiverse WILL NOT receive any
+##                 review or updates from the Ubuntu security team.
+##
+## See the sources.list(5) manual page for further settings.
+`
+
+var ubuntuSourceSecurityHeader = `## Ubuntu security updates. Aside from URIs and Suites,
+## this should mirror your choices in the previous section.
+`
+
+// deb822SourcesList returns the content of /etc/apt/sources.list.d/ubuntu.sources
+// to be used during the build process
+func (i *ImageDefinition) Deb822BuildSourcesList() string {
+	return i.deb822SourcesList(false)
+}
+
+// deb822SourcesList returns the content of /etc/apt/sources.list.d/ubuntu.sources
+// for the target image
+func (i *ImageDefinition) Deb822TargetSourcesList() string {
+	return i.deb822SourcesList(true)
+}
+
+// deb822SourcesList returns the content of /etc/apt/sources.list.d/ubuntu.sources
+// in the deb822 format.
+// The target param defines if the generated sources list will be used in the target image.
+func (i *ImageDefinition) deb822SourcesList(target bool) string {
+	pocket := i.Rootfs.Pocket
+	if target {
+		pocket = i.Customization.Pocket
+	}
+	pocket = strings.ToLower(pocket)
+
+	ubuntuSources := ubuntuSourceHeader + generateDeb822Section(
+		i.Rootfs.Mirror,
+		i.Series,
+		i.Rootfs.Components,
+		pocket,
+	)
+
+	ubuntuSources += ubuntuSourceSecurityHeader + generateDeb822Section(
+		i.securityMirror(),
+		i.Series,
+		i.Rootfs.Components,
+		pocket,
+	)
+
+	return ubuntuSources
 }
diff --git a/internal/imagedefinition/image_definition_test.go b/internal/imagedefinition/image_definition_test.go
index 61e10366..d540a0da 100644
--- a/internal/imagedefinition/image_definition_test.go
+++ b/internal/imagedefinition/image_definition_test.go
@@ -12,6 +12,7 @@ import (
 
 func TestGeneratePocketList(t *testing.T) {
 	t.Parallel()
+	asserter := helper.Asserter{T: t}
 	type args struct {
 		series         string
 		components     []string
@@ -21,10 +22,10 @@ func TestGeneratePocketList(t *testing.T) {
 	}
 
 	testCases := []struct {
-		name            string
-		imageDef        ImageDefinition
-		args            args
-		expectedPockets []string
+		name                string
+		imageDef            ImageDefinition
+		args                args
+		expectedSourcesList string
 	}{
 		{
 			name: "release",
@@ -35,7 +36,10 @@ func TestGeneratePocketList(t *testing.T) {
 				securityMirror: "http://security.ubuntu.com/ubuntu/",
 				pocket:         "release",
 			},
-			expectedPockets: []string{"deb http://archive.ubuntu.com/ubuntu/ jammy main universe\n"},
+			expectedSourcesList: `# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
+# newer versions of the distribution.
+deb http://archive.ubuntu.com/ubuntu/ jammy main universe
+`,
 		},
 		{
 			name: "security",
@@ -46,10 +50,11 @@ func TestGeneratePocketList(t *testing.T) {
 				pocket:         "security",
 				securityMirror: "http://security.ubuntu.com/ubuntu/",
 			},
-			expectedPockets: []string{
-				"deb http://archive.ubuntu.com/ubuntu/ jammy main\n",
-				"deb http://security.ubuntu.com/ubuntu/ jammy-security main\n",
-			},
+			expectedSourcesList: `# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
+# newer versions of the distribution.
+deb http://archive.ubuntu.com/ubuntu/ jammy main
+deb http://security.ubuntu.com/ubuntu/ jammy-security main
+`,
 		},
 		{
 			name: "updates",
@@ -60,11 +65,14 @@ func TestGeneratePocketList(t *testing.T) {
 				securityMirror: "http://ports.ubuntu.com/",
 				pocket:         "updates",
 			},
-			expectedPockets: []string{
-				"deb http://ports.ubuntu.com/ jammy main universe multiverse\n",
-				"deb http://ports.ubuntu.com/ jammy-security main universe multiverse\n",
-				"deb http://ports.ubuntu.com/ jammy-updates main universe multiverse\n",
-			},
+			expectedSourcesList: `# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
+# newer versions of the distribution.
+deb http://ports.ubuntu.com/ jammy main universe multiverse
+deb http://ports.ubuntu.com/ jammy-security main universe multiverse
+## Major bug fix updates produced after the final release of the
+## distribution.
+deb http://ports.ubuntu.com/ jammy-updates main universe multiverse
+`,
 		},
 		{
 			name: "proposed",
@@ -75,34 +83,28 @@ func TestGeneratePocketList(t *testing.T) {
 				securityMirror: "http://security.ubuntu.com/ubuntu/",
 				pocket:         "proposed",
 			},
-			expectedPockets: []string{
-				"deb http://archive.ubuntu.com/ubuntu/ jammy main universe multiverse restricted\n",
-				"deb http://security.ubuntu.com/ubuntu/ jammy-security main universe multiverse restricted\n",
-				"deb http://archive.ubuntu.com/ubuntu/ jammy-updates main universe multiverse restricted\n",
-				"deb http://archive.ubuntu.com/ubuntu/ jammy-proposed main universe multiverse restricted\n",
-			},
+			expectedSourcesList: `# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
+# newer versions of the distribution.
+deb http://archive.ubuntu.com/ubuntu/ jammy main universe multiverse restricted
+deb http://security.ubuntu.com/ubuntu/ jammy-security main universe multiverse restricted
+## Major bug fix updates produced after the final release of the
+## distribution.
+deb http://archive.ubuntu.com/ubuntu/ jammy-updates main universe multiverse restricted
+deb http://archive.ubuntu.com/ubuntu/ jammy-proposed main universe multiverse restricted
+`,
 		},
 	}
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
-			pocketList := generatePocketList(
+			gotSourcesList := generateLegacySourcesList(
 				tc.args.series,
 				tc.args.components,
 				tc.args.mirror,
 				tc.args.securityMirror,
 				tc.args.pocket,
 			)
-			for _, expectedPocket := range tc.expectedPockets {
-				found := false
-				for _, pocket := range pocketList {
-					if pocket == expectedPocket {
-						found = true
-					}
-				}
-				if !found {
-					t.Errorf("Expected %s in pockets list %s, but it was not", expectedPocket, pocketList)
-				}
-			}
+
+			asserter.AssertEqual(tc.expectedSourcesList, gotSourcesList)
 		})
 	}
 }
@@ -204,12 +206,13 @@ func TestImageDefinition_SetDefaults(t *testing.T) {
 			Seed: &Seed{
 				Vcs: helper.BoolPtr(true),
 			},
-			Tarball:    &Tarball{},
-			Components: []string{"main", "restricted"},
-			Archive:    "ubuntu",
-			Flavor:     "ubuntu",
-			Mirror:     "http://archive.ubuntu.com/ubuntu/",
-			Pocket:     "release",
+			Tarball:           &Tarball{},
+			Components:        []string{"main", "restricted"},
+			Archive:           "ubuntu",
+			Flavor:            "ubuntu",
+			Mirror:            "http://archive.ubuntu.com/ubuntu/",
+			Pocket:            "release",
+			SourcesListDeb822: helper.BoolPtr(false),
 		},
 		Customization: &Customization{
 			Components: []string{"main", "restricted", "universe"},
@@ -316,3 +319,105 @@ func TestImageDefinition_securityMirror(t *testing.T) {
 		})
 	}
 }
+
+func Test_generateDeb822Section(t *testing.T) {
+	asserter := helper.Asserter{T: t}
+	type args struct {
+		mirror     string
+		series     string
+		components []string
+		pocket     string
+	}
+	tests := []struct {
+		name string
+		args args
+		want string
+	}{
+		{
+			name: "release",
+			args: args{
+				mirror:     "http://archive.ubuntu.com/ubuntu/",
+				series:     "jammy",
+				components: []string{"main", "restricted"},
+				pocket:     "release",
+			},
+			want: `Types: deb
+URIs: http://archive.ubuntu.com/ubuntu/
+Suites: jammy
+Components: main restricted
+Signed-By: /usr/share/keyrings/ubuntu-archive-keyring.gpg
+
+`,
+		},
+		{
+			name: "security",
+			args: args{
+				mirror:     "http://security.ubuntu.com/ubuntu/",
+				series:     "jammy",
+				components: []string{"main", "restricted"},
+				pocket:     "security",
+			},
+			want: `Types: deb
+URIs: http://security.ubuntu.com/ubuntu/
+Suites: jammy-security
+Components: main restricted
+Signed-By: /usr/share/keyrings/ubuntu-archive-keyring.gpg
+
+`,
+		},
+		{
+			name: "proposed",
+			args: args{
+				mirror:     "http://archive.ubuntu.com/ubuntu/",
+				series:     "jammy",
+				components: []string{"main", "restricted"},
+				pocket:     "proposed",
+			},
+			want: `Types: deb
+URIs: http://archive.ubuntu.com/ubuntu/
+Suites: jammy jammy-updates jammy-proposed
+Components: main restricted
+Signed-By: /usr/share/keyrings/ubuntu-archive-keyring.gpg
+
+`,
+		},
+		{
+			name: "updates",
+			args: args{
+				mirror:     "http://archive.ubuntu.com/ubuntu/",
+				series:     "jammy",
+				components: []string{"main", "restricted"},
+				pocket:     "updates",
+			},
+			want: `Types: deb
+URIs: http://archive.ubuntu.com/ubuntu/
+Suites: jammy jammy-updates
+Components: main restricted
+Signed-By: /usr/share/keyrings/ubuntu-archive-keyring.gpg
+
+`,
+		},
+		{
+			name: "no pocket",
+			args: args{
+				mirror:     "http://archive.ubuntu.com/ubuntu/",
+				series:     "jammy",
+				components: []string{"main", "restricted"},
+				pocket:     "",
+			},
+			want: `Types: deb
+URIs: http://archive.ubuntu.com/ubuntu/
+Suites: 
+Components: main restricted
+Signed-By: /usr/share/keyrings/ubuntu-archive-keyring.gpg
+
+`,
+		},
+	}
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			got := generateDeb822Section(tc.args.mirror, tc.args.series, tc.args.components, tc.args.pocket)
+			asserter.AssertEqual(tc.want, got)
+		})
+	}
+}
diff --git a/internal/statemachine/classic.go b/internal/statemachine/classic.go
index 6a8ba030..adaab0c2 100644
--- a/internal/statemachine/classic.go
+++ b/internal/statemachine/classic.go
@@ -92,12 +92,20 @@ func (stateMachine *StateMachine) parseImageDefinition() error {
 		return err
 	}
 
+	if imageDefinition.Rootfs.SourcesListDeb822 == nil {
+		fmt.Print("WARNING: rootfs.sources-list-deb822 was not set. Please explicitely set the format desired for sources list in your image definition.\n")
+	}
+
 	// populate the default values for imageDefinition if they were not provided in
 	// the image definition YAML file
 	if err := helperSetDefaults(&imageDefinition); err != nil {
 		return err
 	}
 
+	if !*imageDefinition.Rootfs.SourcesListDeb822 {
+		fmt.Print("WARNING: rootfs.sources-list-deb822 is set to false. The deprecated format will be used to manage sources list. Please if possible adopt the new format.\n")
+	}
+
 	// The official standard for YAML schemas states that they are an extension of
 	// JSON schema draft 4. We therefore validate the decoded YAML against a JSON
 	// schema. The workflow is as follows:
diff --git a/internal/statemachine/classic_states.go b/internal/statemachine/classic_states.go
index 8a841431..3469e283 100644
--- a/internal/statemachine/classic_states.go
+++ b/internal/statemachine/classic_states.go
@@ -176,8 +176,15 @@ func (stateMachine *StateMachine) createChroot() error {
 		return fmt.Errorf("Error truncating resolv.conf: %s", err.Error())
 	}
 
-	// add any extra apt sources to /etc/apt/sources.list
-	return stateMachine.overwriteSourcesList(classicStateMachine.ImageDef.BuildPocketList())
+	if *classicStateMachine.ImageDef.Rootfs.SourcesListDeb822 {
+		err := stateMachine.setDeb822SourcesList(classicStateMachine.ImageDef.Deb822BuildSourcesList())
+		if err != nil {
+			return err
+		}
+		return stateMachine.setLegacySourcesList(imagedefinition.LegacySourcesListComment)
+	}
+
+	return stateMachine.setLegacySourcesList(classicStateMachine.ImageDef.LegacyBuildSourcesList())
 }
 
 // add PPAs to the apt sources list
@@ -959,27 +966,58 @@ func (stateMachine *StateMachine) populateClassicRootfsContents() error {
 // is done, and before other manual customization to let users modify it.
 func (stateMachine *StateMachine) customizeSourcesList() error {
 	classicStateMachine := stateMachine.parent.(*ClassicStateMachine)
-	return stateMachine.overwriteSourcesList(classicStateMachine.ImageDef.TargetPocketList())
+
+	if *classicStateMachine.ImageDef.Rootfs.SourcesListDeb822 {
+		err := stateMachine.setDeb822SourcesList(classicStateMachine.ImageDef.Deb822TargetSourcesList())
+		if err != nil {
+			return err
+		}
+		return stateMachine.setLegacySourcesList(imagedefinition.LegacySourcesListComment)
+	}
+
+	return stateMachine.setLegacySourcesList(classicStateMachine.ImageDef.LegacyTargetSourcesList())
 }
 
-// overwriteSourcesList replaces /etc/apt/sources.list with the given list of entries
+// setLegacySourcesList replaces /etc/apt/sources.list with the given list of entries
 // This function will truncate the existing file.
-func (stateMachine *StateMachine) overwriteSourcesList(aptSources []string) error {
+func (stateMachine *StateMachine) setLegacySourcesList(aptSources string) error {
 	sourcesList := filepath.Join(stateMachine.tempDirs.chroot, "etc", "apt", "sources.list")
 	sourcesListFile, err := osOpenFile(sourcesList, os.O_TRUNC|os.O_WRONLY, 0644)
 	if err != nil {
 		return fmt.Errorf("unable to open sources.list file: %w", err)
 	}
 	defer sourcesListFile.Close()
-	for _, aptSource := range aptSources {
-		_, err = sourcesListFile.WriteString(aptSource)
-		if err != nil {
-			return fmt.Errorf("unable to write apt sources: %w", err)
-		}
+	_, err = sourcesListFile.WriteString(aptSources)
+	if err != nil {
+		return fmt.Errorf("unable to write apt sources: %w", err)
 	}
 	return nil
 }
 
+// setDeb822SourcesList replaces /etc/apt/sources.list.d/ubuntu.sources with the given content
+// This function will truncate the existing file if any
+func (stateMachine *StateMachine) setDeb822SourcesList(sourcesListContent string) error {
+	sourcesListDir := filepath.Join(stateMachine.tempDirs.chroot, "etc", "apt", "sources.list.d")
+	err := osMkdirAll(sourcesListDir, 0755)
+	if err != nil && !os.IsExist(err) {
+		return fmt.Errorf("Error /etc/apt/sources.list.d directory: %s", err.Error())
+	}
+
+	sourcesList := filepath.Join(sourcesListDir, "ubuntu.sources")
+	f, err := osOpenFile(sourcesList, os.O_CREATE|os.O_TRUNC|os.O_WRONLY, 0644)
+	if err != nil {
+		return fmt.Errorf("unable to open ubuntu.sources file: %w", err)
+	}
+	defer f.Close()
+
+	_, err = f.WriteString(sourcesListContent)
+	if err != nil {
+		return fmt.Errorf("unable to write apt sources: %w", err)
+	}
+
+	return nil
+}
+
 // fixFstab makes sure the fstab contains a valid entry for the root mount point
 func (stateMachine *StateMachine) fixFstab() error {
 	classicStateMachine := stateMachine.parent.(*ClassicStateMachine)
diff --git a/internal/statemachine/classic_test.go b/internal/statemachine/classic_test.go
index 21609072..4005f3b8 100644
--- a/internal/statemachine/classic_test.go
+++ b/internal/statemachine/classic_test.go
@@ -2264,42 +2264,55 @@ func TestStateMachine_FailedPopulateClassicRootfsContents(t *testing.T) {
 // TestSateMachine_customizeSourcesList tests functionality of the customizeSourcesList state function
 func TestSateMachine_customizeSourcesList(t *testing.T) {
 	testCases := []struct {
-		name                string
-		existingSourcesList string
-		customization       *imagedefinition.Customization
-		mockFuncs           func() func()
-		expectedErr         string
-		expectedSourcesList string
+		name                      string
+		deb822Format              bool
+		existingSourcesList       string
+		existingDeb822SourcesList string
+		customization             *imagedefinition.Customization
+		mockFuncs                 func() func()
+		expectedErr               string
+		expectedSourcesList       string
+		expectedDeb822SourcesList string
 	}{
 		{
-			name:                "set default",
+			name:                "set default sources.list",
+			deb822Format:        false,
 			existingSourcesList: "deb http://ports.ubuntu.com/ubuntu-ports jammy main restricted",
 			customization:       &imagedefinition.Customization{},
-			expectedSourcesList: `deb http://archive.ubuntu.com/ubuntu/ jammy main restricted universe
+			expectedSourcesList: `# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
+# newer versions of the distribution.
+deb http://archive.ubuntu.com/ubuntu/ jammy main restricted universe
 `,
 		},
 		{
-			name:                "set less components",
+			name:                "set less components sources.list",
+			deb822Format:        false,
 			existingSourcesList: "deb http://ports.ubuntu.com/ubuntu-ports jammy main restricted",
 			customization: &imagedefinition.Customization{
 				Components: []string{"main"},
 			},
-			expectedSourcesList: `deb http://archive.ubuntu.com/ubuntu/ jammy main
+			expectedSourcesList: `# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
+# newer versions of the distribution.
+deb http://archive.ubuntu.com/ubuntu/ jammy main
 `,
 		},
 		{
-			name:                "set components and pocket",
+			name:                "set components and pocket sources.list",
+			deb822Format:        false,
 			existingSourcesList: "deb http://ports.ubuntu.com/ubuntu-ports jammy main restricted",
 			customization: &imagedefinition.Customization{
 				Components: []string{"main"},
 				Pocket:     "security",
 			},
-			expectedSourcesList: `deb http://archive.ubuntu.com/ubuntu/ jammy main
+			expectedSourcesList: `# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
+# newer versions of the distribution.
+deb http://archive.ubuntu.com/ubuntu/ jammy main
 deb http://security.ubuntu.com/ubuntu/ jammy-security main
 `,
 		},
 		{
 			name:                "fail to write sources.list",
+			deb822Format:        false,
 			existingSourcesList: "deb http://ports.ubuntu.com/ubuntu-ports jammy main restricted",
 			customization: &imagedefinition.Customization{
 				Components: []string{"main"},
@@ -2318,6 +2331,123 @@ deb http://security.ubuntu.com/ubuntu/ jammy-security main
 				return func() { osOpenFile = os.OpenFile }
 			},
 		},
+		{
+			name:                "set default ubuntu.sources and commented sources.list",
+			deb822Format:        true,
+			existingSourcesList: "deb http://ports.ubuntu.com/ubuntu-ports jammy main restricted",
+			existingDeb822SourcesList: `Types: deb
+URIs: http://archive.ubuntu.com/
+Suites: jammy
+Components: main universe restricted multiverse
+Signed-By: /usr/share/keyrings/ubuntu-archive-keyring.gpg
+`,
+			customization:       &imagedefinition.Customization{},
+			expectedSourcesList: imagedefinition.LegacySourcesListComment,
+			expectedDeb822SourcesList: `## Ubuntu distribution repository
+##
+## The following settings can be adjusted to configure which packages to use from Ubuntu.
+## Mirror your choices (except for URIs and Suites) in the security section below to
+## ensure timely security updates.
+##
+## Types: Append deb-src to enable the fetching of source package.
+## URIs: A URL to the repository (you may add multiple URLs)
+## Suites: The following additional suites can be configured
+##   <name>-updates   - Major bug fix updates produced after the final release of the
+##                      distribution.
+##   <name>-backports - software from this repository may not have been tested as
+##                      extensively as that contained in the main release, although it includes
+##                      newer versions of some applications which may provide useful features.
+##                      Also, please note that software in backports WILL NOT receive any review
+##                      or updates from the Ubuntu security team.
+## Components: Aside from main, the following components can be added to the list
+##   restricted  - Software that may not be under a free license, or protected by patents.
+##   universe    - Community maintained packages.
+##                 Software from this repository is only maintained and supported by Canonical
+##                 for machines with Ubuntu Pro subscriptions. Without Ubuntu Pro, the Ubuntu
+##                 community provides best-effort security maintenance.
+##   multiverse  - Community maintained of restricted. Software from this repository is
+##                 ENTIRELY UNSUPPORTED by the Ubuntu team, and may not be under a free
+##                 licence. Please satisfy yourself as to your rights to use the software.
+##                 Also, please note that software in multiverse WILL NOT receive any
+##                 review or updates from the Ubuntu security team.
+##
+## See the sources.list(5) manual page for further settings.
+Types: deb
+URIs: http://archive.ubuntu.com/ubuntu/
+Suites: jammy
+Components: main restricted
+Signed-By: /usr/share/keyrings/ubuntu-archive-keyring.gpg
+
+## Ubuntu security updates. Aside from URIs and Suites,
+## this should mirror your choices in the previous section.
+Types: deb
+URIs: http://security.ubuntu.com/ubuntu/
+Suites: jammy
+Components: main restricted
+Signed-By: /usr/share/keyrings/ubuntu-archive-keyring.gpg
+
+`,
+		},
+		{
+			name:                "fail to write ubuntu.sources and commented sources.list",
+			deb822Format:        true,
+			existingSourcesList: "deb http://ports.ubuntu.com/ubuntu-ports jammy main restricted",
+			existingDeb822SourcesList: `Types: deb
+URIs: http://archive.ubuntu.com/
+Suites: jammy
+Components: main universe restricted multiverse
+Signed-By: /usr/share/keyrings/ubuntu-archive-keyring.gpg
+`,
+			customization:       &imagedefinition.Customization{},
+			expectedSourcesList: "deb http://ports.ubuntu.com/ubuntu-ports jammy main restricted",
+			expectedDeb822SourcesList: `Types: deb
+URIs: http://archive.ubuntu.com/
+Suites: jammy
+Components: main universe restricted multiverse
+Signed-By: /usr/share/keyrings/ubuntu-archive-keyring.gpg
+`,
+			expectedErr: "unable to open ubuntu.sources file",
+			mockFuncs: func() func() {
+				mock := NewOSMock(
+					&osMockConf{
+						OpenFileThreshold: 0,
+					},
+				)
+
+				osOpenFile = mock.OpenFile
+				return func() { osOpenFile = os.OpenFile }
+			},
+		},
+		{
+			name:                "fail to create sources.list.d",
+			deb822Format:        true,
+			existingSourcesList: "deb http://ports.ubuntu.com/ubuntu-ports jammy main restricted",
+			existingDeb822SourcesList: `Types: deb
+URIs: http://archive.ubuntu.com/
+Suites: jammy
+Components: main universe restricted multiverse
+Signed-By: /usr/share/keyrings/ubuntu-archive-keyring.gpg
+`,
+			customization:       &imagedefinition.Customization{},
+			expectedSourcesList: "deb http://ports.ubuntu.com/ubuntu-ports jammy main restricted",
+			expectedDeb822SourcesList: `Types: deb
+URIs: http://archive.ubuntu.com/
+Suites: jammy
+Components: main universe restricted multiverse
+Signed-By: /usr/share/keyrings/ubuntu-archive-keyring.gpg
+`,
+			expectedErr: "Error /etc/apt/sources.list.d directory",
+			mockFuncs: func() func() {
+				mock := NewOSMock(
+					&osMockConf{
+						MkdirAllThreshold: 0,
+					},
+				)
+
+				osMkdirAll = mock.MkdirAll
+				return func() { osMkdirAll = os.MkdirAll }
+			},
+		},
 	}
 
 	for _, tc := range testCases {
@@ -2330,9 +2460,11 @@ deb http://security.ubuntu.com/ubuntu/ jammy-security main
 			stateMachine.commonFlags, stateMachine.stateMachineFlags = helper.InitCommonOpts()
 			stateMachine.parent = &stateMachine
 			stateMachine.ImageDef = imagedefinition.ImageDefinition{
-				Architecture:  getHostArch(),
-				Series:        getHostSuite(),
-				Rootfs:        &imagedefinition.Rootfs{},
+				Architecture: getHostArch(),
+				Series:       getHostSuite(),
+				Rootfs: &imagedefinition.Rootfs{
+					SourcesListDeb822: helper.BoolPtr(tc.deb822Format),
+				},
 				Customization: tc.customization,
 			}
 
@@ -2344,14 +2476,18 @@ deb http://security.ubuntu.com/ubuntu/ jammy-security main
 
 			t.Cleanup(func() { os.RemoveAll(stateMachine.stateMachineFlags.WorkDir) })
 
-			err = os.MkdirAll(filepath.Join(stateMachine.tempDirs.chroot, "etc", "apt"), 0644)
+			err = os.MkdirAll(filepath.Join(stateMachine.tempDirs.chroot, "etc", "apt", "sources.list.d"), 0644)
 			asserter.AssertErrNil(err, true)
 
 			sourcesListPath := filepath.Join(stateMachine.tempDirs.chroot, "etc", "apt", "sources.list")
+			deb822SourcesListPath := filepath.Join(stateMachine.tempDirs.chroot, "etc", "apt", "sources.list.d", "ubuntu.sources")
 
 			err = osWriteFile(sourcesListPath, []byte(tc.existingSourcesList), 0644)
 			asserter.AssertErrNil(err, true)
 
+			err = osWriteFile(deb822SourcesListPath, []byte(tc.existingDeb822SourcesList), 0644)
+			asserter.AssertErrNil(err, true)
+
 			if tc.mockFuncs != nil {
 				restoreMock := tc.mockFuncs()
 				t.Cleanup(restoreMock)
@@ -2365,10 +2501,13 @@ deb http://security.ubuntu.com/ubuntu/ jammy-security main
 			sourcesListBytes, err := os.ReadFile(sourcesListPath)
 			asserter.AssertErrNil(err, true)
 
-			if string(sourcesListBytes) != tc.expectedSourcesList {
-				t.Errorf("Expected sources.list content \"%s\", but got \"%s\"",
-					tc.expectedSourcesList, string(sourcesListBytes))
-			}
+			asserter.AssertEqual(tc.expectedSourcesList, string(sourcesListBytes))
+
+			deb822SourcesListBytes, err := os.ReadFile(deb822SourcesListPath)
+			asserter.AssertErrNil(err, true)
+
+			asserter.AssertEqual(tc.expectedDeb822SourcesList, string(deb822SourcesListBytes))
+
 		})
 	}
 }
@@ -2994,15 +3133,59 @@ func TestSuccessfulClassicRun(t *testing.T) {
 		t.Errorf("Expected LANG=C.UTF-8 in %s, but got %s", localeFile, string(localeBytes))
 	}
 
+	// check if components and pocket correctly setup in /etc/apt/sources.list.d/ubuntu.sources
+	aptDeb822SourcesListBytes, err := os.ReadFile(filepath.Join(mountDir, "etc", "apt", "sources.list.d", "ubuntu.sources"))
+	asserter.AssertErrNil(err, true)
+	wantAptDeb822SourcesList := `## Ubuntu distribution repository
+##
+## The following settings can be adjusted to configure which packages to use from Ubuntu.
+## Mirror your choices (except for URIs and Suites) in the security section below to
+## ensure timely security updates.
+##
+## Types: Append deb-src to enable the fetching of source package.
+## URIs: A URL to the repository (you may add multiple URLs)
+## Suites: The following additional suites can be configured
+##   <name>-updates   - Major bug fix updates produced after the final release of the
+##                      distribution.
+##   <name>-backports - software from this repository may not have been tested as
+##                      extensively as that contained in the main release, although it includes
+##                      newer versions of some applications which may provide useful features.
+##                      Also, please note that software in backports WILL NOT receive any review
+##                      or updates from the Ubuntu security team.
+## Components: Aside from main, the following components can be added to the list
+##   restricted  - Software that may not be under a free license, or protected by patents.
+##   universe    - Community maintained packages.
+##                 Software from this repository is only maintained and supported by Canonical
+##                 for machines with Ubuntu Pro subscriptions. Without Ubuntu Pro, the Ubuntu
+##                 community provides best-effort security maintenance.
+##   multiverse  - Community maintained of restricted. Software from this repository is
+##                 ENTIRELY UNSUPPORTED by the Ubuntu team, and may not be under a free
+##                 licence. Please satisfy yourself as to your rights to use the software.
+##                 Also, please note that software in multiverse WILL NOT receive any
+##                 review or updates from the Ubuntu security team.
+##
+## See the sources.list(5) manual page for further settings.
+Types: deb
+URIs: http://archive.ubuntu.com/ubuntu/
+Suites: jammy
+Components: main universe restricted
+Signed-By: /usr/share/keyrings/ubuntu-archive-keyring.gpg
+
+## Ubuntu security updates. Aside from URIs and Suites,
+## this should mirror your choices in the previous section.
+Types: deb
+URIs: http://security.ubuntu.com/ubuntu/
+Suites: jammy
+Components: main restricted
+Signed-By: /usr/share/keyrings/ubuntu-archive-keyring.gpg
+
+`
+	asserter.AssertEqual(wantAptDeb822SourcesList, string(aptDeb822SourcesListBytes))
+
 	// check if components and pocket correctly setup in /etc/apt/sources.list
 	aptSourcesListBytes, err := os.ReadFile(filepath.Join(mountDir, "etc", "apt", "sources.list"))
 	asserter.AssertErrNil(err, true)
-	wantAptSourcesList := `deb http://archive.ubuntu.com/ubuntu/ jammy main universe restricted multiverse
-deb http://security.ubuntu.com/ubuntu/ jammy-security main universe restricted multiverse
-deb http://archive.ubuntu.com/ubuntu/ jammy-updates main universe restricted multiverse
-deb http://archive.ubuntu.com/ubuntu/ jammy-proposed main universe restricted multiverse
-`
-	asserter.AssertEqual(wantAptSourcesList, string(aptSourcesListBytes))
+	asserter.AssertEqual(imagedefinition.LegacySourcesListComment, string(aptSourcesListBytes))
 
 }
 
@@ -3716,6 +3899,7 @@ func TestCreateChroot(t *testing.T) {
 			t.Errorf("%s is not present in /etc/apt/sources.list", pocket)
 		}
 	}
+
 }
 
 // TestFailedCreateChroot tests failure cases in createChroot
@@ -3733,7 +3917,9 @@ func TestFailedCreateChroot(t *testing.T) {
 	stateMachine.ImageDef = imagedefinition.ImageDefinition{
 		Architecture: getHostArch(),
 		Series:       getHostSuite(),
-		Rootfs:       &imagedefinition.Rootfs{},
+		Rootfs: &imagedefinition.Rootfs{
+			SourcesListDeb822: helper.BoolPtr(false),
+		},
 	}
 
 	err := stateMachine.makeTemporaryDirectories()
diff --git a/internal/statemachine/testdata/image_definitions/test_amd64.yaml b/internal/statemachine/testdata/image_definitions/test_amd64.yaml
index 48696a75..b8e92341 100644
--- a/internal/statemachine/testdata/image_definitions/test_amd64.yaml
+++ b/internal/statemachine/testdata/image_definitions/test_amd64.yaml
@@ -14,6 +14,7 @@ rootfs:
     - main
     - universe
     - restricted
+  sources-list-deb822: true
   seed:
     urls:
       - "git://git.launchpad.net/~ubuntu-core-dev/ubuntu-seeds/+git/"
diff --git a/internal/statemachine/testdata/image_definitions/test_build_gadget.yaml b/internal/statemachine/testdata/image_definitions/test_build_gadget.yaml
index 64d9d3c3..51c88ae2 100644
--- a/internal/statemachine/testdata/image_definitions/test_build_gadget.yaml
+++ b/internal/statemachine/testdata/image_definitions/test_build_gadget.yaml
@@ -10,6 +10,7 @@ gadget:
   branch: classic
   type: "git"
 rootfs:
+  sources-list-deb822: true
   seed:
     urls:
       - "https://git.launchpad.net/~ubuntu-core-dev/ubuntu-seeds/+git/"
diff --git a/internal/statemachine/testdata/image_definitions/test_customization.yaml b/internal/statemachine/testdata/image_definitions/test_customization.yaml
index 3f3dd5d6..d29f1f9e 100644
--- a/internal/statemachine/testdata/image_definitions/test_customization.yaml
+++ b/internal/statemachine/testdata/image_definitions/test_customization.yaml
@@ -10,6 +10,7 @@ gadget:
   branch: classic
   type: "git"
 rootfs:
+  sources-list-deb822: true
   seed:
     urls:
       - "https://git.launchpad.net/~ubuntu-core-dev/ubuntu-seeds/+git/"
diff --git a/internal/statemachine/tests_helper_test.go b/internal/statemachine/tests_helper_test.go
index 9bd53c49..1b729985 100644
--- a/internal/statemachine/tests_helper_test.go
+++ b/internal/statemachine/tests_helper_test.go
@@ -19,7 +19,8 @@ var basicImageDef = imagedefinition.ImageDefinition{
 	Architecture: getHostArch(),
 	Series:       getHostSuite(),
 	Rootfs: &imagedefinition.Rootfs{
-		Archive: "ubuntu",
+		Archive:           "ubuntu",
+		SourcesListDeb822: helper.BoolPtr(false),
 	},
 	Customization: &imagedefinition.Customization{},
 }
@@ -115,6 +116,7 @@ type osMockConf struct {
 	RemoveThreshold                uint
 	TruncateThreshold              uint
 	OpenFileThreshold              uint
+	MkdirAllThreshold              uint
 }
 
 // osMock holds methods to easily mock functions from os and snapd/osutil packages
@@ -128,6 +130,7 @@ type osMock struct {
 	beforeRemoveFail                uint
 	beforeTruncateFail              uint
 	beforeOpenFileFail              uint
+	beforeMkdirAllFail              uint
 }
 
 func (o *osMock) CopySpecialFile(path, dest string) error {
@@ -175,6 +178,15 @@ func (o *osMock) OpenFile(name string, flag int, perm os.FileMode) (*os.File, er
 	return &os.File{}, nil
 }
 
+func (o *osMock) MkdirAll(path string, perm os.FileMode) error {
+	if o.beforeOpenFileFail >= o.conf.OpenFileThreshold {
+		return fmt.Errorf("OpenFile fail")
+	}
+	o.beforeMkdirAllFail++
+
+	return nil
+}
+
 func NewOSMock(conf *osMockConf) *osMock {
 	return &osMock{conf: conf}
 }