diff --git a/packages/router/src/navigation_transition.ts b/packages/router/src/navigation_transition.ts
index 860889e1063..e5677366d90 100644
--- a/packages/router/src/navigation_transition.ts
+++ b/packages/router/src/navigation_transition.ts
@@ -272,6 +272,7 @@ interface InternalRouterInterface {
   ngModule: NgModuleRef<any>;
   readonly routerState: RouterState;
   errorHandler: ErrorHandler;
+  malformedUriErrorHandler: (error: URIError, urlSerializer: UrlSerializer, url: string) => UrlTree;
   navigated: boolean;
   afterPreactivation: () => Observable<void>;
   urlHandlingStrategy: UrlHandlingStrategy;