diff --git a/knockout/index.d.ts b/knockout/index.d.ts
index 3db35f7578..970a4e9a08 100644
--- a/knockout/index.d.ts
+++ b/knockout/index.d.ts
@@ -587,6 +587,12 @@ interface KnockoutStatic {
     /////////////////////////////////
 
     tasks: KnockoutTasks;
+    
+    /////////////////////////////////
+    // utils.js
+    /////////////////////////////////
+
+    onError?: (error: Error) => void;
 }
 
 interface KnockoutBindingProvider {