diff --git a/chai/chai-tests.ts b/chai/chai-tests.ts
index 398ebd069d..98d75e8aef 100644
--- a/chai/chai-tests.ts
+++ b/chai/chai-tests.ts
@@ -772,7 +772,7 @@ function members() {
 //tdd
 declare function suite(description: string, action: Function):void;
 declare function test(description: string, action: Function):void;
-declare function err(action: any, msg?: string):void;
+
 interface FieldObj {
 	field: any;
 }