diff --git a/modules/system/system.admin.inc b/modules/system/system.admin.inc
index 431a412428b18dfb531e62da45e4b7c16e8cf3b3..0c2ac099f6279d03f13d0e66f517bf91cd0c105a 100644
--- a/modules/system/system.admin.inc
+++ b/modules/system/system.admin.inc
@@ -1346,7 +1346,6 @@ function system_modules_uninstall_submit($form, &$form_state) {
  *   use as the default value of the IP address form field.
  */
 function system_ip_blocking($default_ip = '') {
-  $output = '';
   $rows = array();
   $header = array(t('Blocked IP addresses'), t('Operations'));
   $result = db_query('SELECT * FROM {blocked_ips}');