diff --git a/src/basic/env-util.h b/src/basic/env-util.h
index e4084af9a53..2bf0603f212 100644
--- a/src/basic/env-util.h
+++ b/src/basic/env-util.h
@@ -69,6 +69,4 @@ int setenv_systemd_exec_pid(bool update_only);
  * PATH-like colon-separated absolute paths */
 int getenv_path_list(const char *name, char ***ret_paths);
 
-int unsetenv_erase(const char *name);
-
 int getenv_steal_erase(const char *name, char **ret);