diff --git a/assets/theme-i18n.json b/assets/theme-i18n.json
index 1b7a8d0d..8ceaee85 100644
--- a/assets/theme-i18n.json
+++ b/assets/theme-i18n.json
@@ -52,6 +52,13 @@
 				}
 			]
 		},
+		"border": {
+			"radiusSizes": [
+				{
+					"name": "Border radius size name"
+				}
+			]
+		},
 		"blocks": {
 			"*": {
 				"typography": {
@@ -96,6 +103,13 @@
 							"name": "Space size name"
 						}
 					]
+				},
+				"border": {
+					"radiusSizes": [
+						{
+							"name": "Border radius size name"
+						}
+					]
 				}
 			}
 		}
diff --git a/features/makepot.feature b/features/makepot.feature
index c292be88..e874345d 100644
--- a/features/makepot.feature
+++ b/features/makepot.feature
@@ -3696,6 +3696,11 @@ Feature: Generate a POT file of a WordPress project
               "fontSizes": [
                   { "name": "Small", "slug": "small", "size": "13px" }
               ]
+          },
+          "border": {
+            "radiusSizes": [
+              { "slug": "soft", "size": "6px", "name": "Soft corners" }
+            ]
           }
         }
       }
@@ -3732,6 +3737,11 @@ Feature: Generate a POT file of a WordPress project
       msgctxt "Font size name"
       msgid "Small"
       """
+    And the foo-theme/foo-theme.pot file should contain:
+      """
+      msgctxt "Border radius size name"
+      msgid "Soft corners"
+      """
     And the foo-theme/foo-theme.pot file should contain:
       """
       msgctxt "Style variation name"
@@ -3756,6 +3766,11 @@ Feature: Generate a POT file of a WordPress project
                 "palette": [
                   { "slug": "black", "color": "#000000", "name": "Black" }
                 ]
+              },
+              "border": {
+                "radiusSizes": [
+                  { "slug": "soft", "size": "6px", "name": "Soft corners for paragraph" }
+                ]
               }
             }
           }
@@ -3774,6 +3789,11 @@ Feature: Generate a POT file of a WordPress project
       msgctxt "Color name"
       msgid "Black"
       """
+    And the foo-theme/foo-theme.pot file should contain:
+      """
+      msgctxt "Border radius size name"
+      msgid "Soft corners for paragraph"
+      """
 
   Scenario: Extract strings from style variations
     Given an empty foo-theme directory