diff --git a/Tests/LibUnicode/TestUnicodeLocale.cpp b/Tests/LibUnicode/TestUnicodeLocale.cpp
index e0ec45d7fb..fb79b32139 100644
--- a/Tests/LibUnicode/TestUnicodeLocale.cpp
+++ b/Tests/LibUnicode/TestUnicodeLocale.cpp
@@ -394,6 +394,14 @@ TEST_CASE(canonicalize_unicode_locale_id)
     test("EN-SU"sv, "en-RU"sv);
     test("en-810"sv, "en-RU"sv);
     test("EN-810"sv, "en-RU"sv);
+    test("hy-su"sv, "hy-AM"sv);
+    test("HY-SU"sv, "hy-AM"sv);
+    test("hy-810"sv, "hy-AM"sv);
+    test("HY-810"sv, "hy-AM"sv);
+    test("und-Armn-su"sv, "und-Armn-AM"sv);
+    test("UND-ARMN-SU"sv, "und-Armn-AM"sv);
+    test("und-Armn-810"sv, "und-Armn-AM"sv);
+    test("UND-ARMN-810"sv, "und-Armn-AM"sv);
 
     // Script subtag aliases.
     test("en-qaai"sv, "en-Zinh"sv);
diff --git a/Userland/Libraries/LibUnicode/Locale.cpp b/Userland/Libraries/LibUnicode/Locale.cpp
index 88e86ce7f6..9744b97152 100644
--- a/Userland/Libraries/LibUnicode/Locale.cpp
+++ b/Userland/Libraries/LibUnicode/Locale.cpp
@@ -591,13 +591,8 @@ static void transform_unicode_locale_id_to_canonical_syntax(LocaleID& locale_id)
         }
 
         if (language_id.region.has_value()) {
-            if (auto alias = resolve_territory_alias(*language_id.region); alias.has_value()) {
-                auto aliases = alias->split_view(' ');
-
-                // FIXME: Territory subtag aliases should also consult the CLDR likelySubtags.json file.
-                //        For now, implement the spec's recommendation of using just the first alias.
-                language_id.region = aliases[0].to_string();
-            }
+            if (auto alias = resolve_territory_alias(*language_id.region); alias.has_value())
+                language_id.region = resolve_most_likely_territory(language_id, *alias);
         }
 
         quick_sort(language_id.variants);