diff --git a/packages/cubejs-client-core/dist/index.d.ts b/packages/cubejs-client-core/dist/index.d.ts
index 39ad393e0e6c1..c7dc5db838229 100644
--- a/packages/cubejs-client-core/dist/index.d.ts
+++ b/packages/cubejs-client-core/dist/index.d.ts
@@ -12,7 +12,7 @@ export type CubeJSApiOptions = {
 export type LoadMethodOptions = {
   mutexKey?: string;
   mutexObj?: {};
-  progressCallback(result: ProgressResult): void;
+  progressCallback?(result: ProgressResult): void;
   subscribe?: boolean;
 };