diff --git a/packages/router/src/config.ts b/packages/router/src/config.ts
index e739f424c6..6d624b94c9 100644
--- a/packages/router/src/config.ts
+++ b/packages/router/src/config.ts
@@ -97,8 +97,8 @@ export type ResolveData = {
  * @see `Route#loadChildren`.
  * @publicApi
  */
-export type LoadChildrenCallback = () =>
-    Type<any>| NgModuleFactory<any>| Promise<Type<any>>| Observable<Type<any>>;
+export type LoadChildrenCallback = () => Type<any>| NgModuleFactory<any>|
+    Promise<NgModuleFactory<any>>| Promise<Type<any>>| Observable<Type<any>>;
 
 /**
  *
diff --git a/tools/public_api_guard/router/router.d.ts b/tools/public_api_guard/router/router.d.ts
index 3e3098ddf7..a9130c64b7 100644
--- a/tools/public_api_guard/router/router.d.ts
+++ b/tools/public_api_guard/router/router.d.ts
@@ -147,7 +147,7 @@ export declare class GuardsCheckStart extends RouterEvent {
 
 export declare type LoadChildren = string | LoadChildrenCallback;
 
-export declare type LoadChildrenCallback = () => Type<any> | NgModuleFactory<any> | Promise<Type<any>> | Observable<Type<any>>;
+export declare type LoadChildrenCallback = () => Type<any> | NgModuleFactory<any> | Promise<NgModuleFactory<any>> | Promise<Type<any>> | Observable<Type<any>>;
 
 export declare type Navigation = {
     id: number;