diff --git a/Modules/pyexpat.c b/Modules/pyexpat.c
index 7f6d84ad8641ca..9949e185dce9c7 100644
--- a/Modules/pyexpat.c
+++ b/Modules/pyexpat.c
@@ -198,12 +198,14 @@ set_error(pyexpat_state *state, xmlparseobject *self, enum XML_Error code)
     return NULL;
 }
 
+#if XML_COMBINED_VERSION >= 20400
 static PyObject *
 set_invalid_arg(pyexpat_state *state, xmlparseobject *self, const char *errmsg)
 {
     SET_XML_ERROR(state, self, XML_ERROR_INVALID_ARGUMENT, errmsg);
     return NULL;
 }
+#endif
 
 #undef SET_XML_ERROR