diff --git a/lib/datasource/common.ts b/lib/datasource/common.ts
index a8f26f015a..03653f4234 100644
--- a/lib/datasource/common.ts
+++ b/lib/datasource/common.ts
@@ -75,7 +75,6 @@ export interface DatasourceApi {
   getDigest?(config: DigestConfig, newValue?: string): Promise<string | null>;
   getReleases(config: GetReleasesConfig): Promise<ReleaseResult | null>;
   defaultRegistryUrls?: string[];
-  appendRegistryUrls?: string[];
   defaultConfig?: Record<string, unknown>;
   registryStrategy?: 'first' | 'hunt' | 'merge';
 }
diff --git a/lib/datasource/index.ts b/lib/datasource/index.ts
index 2aa1554f0d..6169abc8d6 100644
--- a/lib/datasource/index.ts
+++ b/lib/datasource/index.ts
@@ -151,13 +151,13 @@ function resolveRegistryUrls(
   datasource: Datasource,
   extractedUrls: string[]
 ): string[] {
-  const { defaultRegistryUrls = [], appendRegistryUrls = [] } = datasource;
+  const { defaultRegistryUrls = [] } = datasource;
   const customUrls = extractedUrls?.filter(Boolean);
   let registryUrls: string[];
   if (is.nonEmptyArray(customUrls)) {
-    registryUrls = [...extractedUrls, ...appendRegistryUrls];
+    registryUrls = [...customUrls];
   } else {
-    registryUrls = [...defaultRegistryUrls, ...appendRegistryUrls];
+    registryUrls = [...defaultRegistryUrls];
   }
   return registryUrls.filter(Boolean);
 }