diff --git a/packages/ai/src/providers/images/register-builtins.ts b/packages/ai/src/providers/images/register-builtins.ts
index f7d1adc3..04338f20 100644
--- a/packages/ai/src/providers/images/register-builtins.ts
+++ b/packages/ai/src/providers/images/register-builtins.ts
@@ -1,5 +1,44 @@
 import { registerImagesApiProvider } from "../../images-api-registry.js";
-import { generateImagesOpenRouter } from "./openrouter.js";
+import type { AssistantImages, ImagesContext, ImagesFunction, ImagesModel, ImagesOptions } from "../../types.js";
+import type { generateImagesOpenRouter as generateImagesOpenRouterFunction } from "./openrouter.js";
+
+interface OpenRouterImagesProviderModule {
+	generateImagesOpenRouter: typeof generateImagesOpenRouterFunction;
+}
+
+let openRouterImagesProviderModulePromise: Promise<OpenRouterImagesProviderModule> | undefined;
+
+function createLazyLoadErrorImages(model: ImagesModel<"openrouter-images">, error: unknown): AssistantImages {
+	return {
+		api: model.api,
+		provider: model.provider,
+		model: model.id,
+		output: [],
+		stopReason: "error",
+		errorMessage: error instanceof Error ? error.message : String(error),
+		timestamp: Date.now(),
+	};
+}
+
+function loadOpenRouterImagesProviderModule(): Promise<OpenRouterImagesProviderModule> {
+	openRouterImagesProviderModulePromise ||= import("./openrouter.js").then(
+		(module) => module as OpenRouterImagesProviderModule,
+	);
+	return openRouterImagesProviderModulePromise;
+}
+
+export const generateImagesOpenRouter: ImagesFunction<"openrouter-images", ImagesOptions> = async (
+	model: ImagesModel<"openrouter-images">,
+	context: ImagesContext,
+	options?: ImagesOptions,
+) => {
+	try {
+		const module = await loadOpenRouterImagesProviderModule();
+		return await module.generateImagesOpenRouter(model, context, options);
+	} catch (error) {
+		return createLazyLoadErrorImages(model, error);
+	}
+};
 
 export function registerBuiltInImagesApiProviders(): void {
 	registerImagesApiProvider({