diff --git a/packages/vega4-extension/src/index.ts b/packages/vega4-extension/src/index.ts
index e66903e13605..2332e013107d 100644
--- a/packages/vega4-extension/src/index.ts
+++ b/packages/vega4-extension/src/index.ts
@@ -92,7 +92,10 @@ export class RenderedVega extends Widget implements IRenderMime.IRenderer {
       this._result.view.finalize();
     }
 
+    const path = await this._resolver.resolveUrl('');
+    const baseURL = await this._resolver.getDownloadUrl(path);
     const loader = vega.vega.loader({
+      baseURL,
       http: { credentials: 'same-origin' }
     });
 
diff --git a/packages/vega5-extension/src/index.ts b/packages/vega5-extension/src/index.ts
index e728c3f22c58..8013bac7d54b 100644
--- a/packages/vega5-extension/src/index.ts
+++ b/packages/vega5-extension/src/index.ts
@@ -92,7 +92,10 @@ export class RenderedVega extends Widget implements IRenderMime.IRenderer {
       this._result.view.finalize();
     }
 
+    const path = await this._resolver.resolveUrl('');
+    const baseURL = await this._resolver.getDownloadUrl(path);
     const loader = vega.vega.loader({
+      baseURL,
       http: { credentials: 'same-origin' }
     });
     const sanitize = async (uri: string, options: any) => {