diff --git a/src/objective-c/GRPCClient/GRPCCall+ChannelArg.m b/src/objective-c/GRPCClient/GRPCCall+ChannelArg.m
index f2821f6abc0..5f9932d86dc 100644
--- a/src/objective-c/GRPCClient/GRPCCall+ChannelArg.m
+++ b/src/objective-c/GRPCClient/GRPCCall+ChannelArg.m
@@ -37,8 +37,6 @@
 
 @implementation GRPCCall (ChannelArg)
 
-static NSString *_userAgentPrefix;
-
 + (void)setUserAgentPrefix:(NSString *)userAgentPrefix forHost:(NSString *)host {
   if (!host) {
     [NSException raise:NSInvalidArgumentException