diff --git a/src/www/firewall_rules.php b/src/www/firewall_rules.php
index 299125ab8..483c6f271 100644
--- a/src/www/firewall_rules.php
+++ b/src/www/firewall_rules.php
@@ -659,11 +659,9 @@ $( document ).ready(function() {
                       <?=gettext("No rules are currently defined for this interface"); ?><br />
                       <?=gettext("All incoming connections on this interface will be blocked until you add pass rules."); ?><br /><br />
                 <?php endif; ?>
-                      <?=gettext("Click the"); ?>
-                      <a href="firewall_rules_edit.php?if=<?=$selected_if;?>"  class="btn btn-default btn-xs">
-                        <span class="glyphicon glyphicon-plus"></span>
-                      </a>
-                      <?=gettext(" button to add a new rule.");?></span>
+                      <?= sprintf(gettext("Click the %s button to add a new rule."),
+                                  '<a href="firewall_rules_edit.php?if='.$selected_if.'" class="btn btn-default btn-xs"><span class="glyphicon glyphicon-plus"></span></a>')
+                      ?></span>
                     </td>
                   </tr>
               <?php else: ?>