diff --git a/l3kernel/l3keys.dtx b/l3kernel/l3keys.dtx
index c001193c5e..1e7bc0cf28 100644
--- a/l3kernel/l3keys.dtx
+++ b/l3kernel/l3keys.dtx
@@ -3358,6 +3358,7 @@
       { \prg_return_true: }
       { \prg_return_false: }
   }
+\prg_generate_conditional_variant:Nnn \keys_if_exist:nn { nx } { T , F , TF }
 %    \end{macrocode}
 % \end{macro}
 %