diff --git a/deps/chakrashim/core/lib/Runtime/PlatformAgnostic/RuntimePlatformAgnosticPch.h b/deps/chakrashim/core/lib/Runtime/PlatformAgnostic/RuntimePlatformAgnosticPch.h
index 038952c0945..d3682a1fae3 100644
--- a/deps/chakrashim/core/lib/Runtime/PlatformAgnostic/RuntimePlatformAgnosticPch.h
+++ b/deps/chakrashim/core/lib/Runtime/PlatformAgnostic/RuntimePlatformAgnosticPch.h
@@ -34,6 +34,7 @@
 #define FALSE 0
 #endif
 #else
+#define U_USING_ICU_NAMESPACE 0
 #include <unicode/umachine.h>
 #endif