diff --git a/src/www/firewall_rules_edit.php b/src/www/firewall_rules_edit.php
index 90af1fc69..40139e0ce 100644
--- a/src/www/firewall_rules_edit.php
+++ b/src/www/firewall_rules_edit.php
@@ -236,11 +236,12 @@ if ($_SERVER['REQUEST_METHOD'] === 'GET') {
             }
         }
     }
-    if (!empty($pconfig['gateway']) && is_ipaddr(lookup_gateway_ip_by_name($pconfig['gateway']))) {
-        if ($pconfig['ipprotocol'] == "inet6" && !is_ipaddrv6(lookup_gateway_ip_by_name($pconfig['gateway']))) {
+    $gateways = new \OPNsense\Routing\Gateways(legacy_interfaces_details());
+    if (!empty($pconfig['gateway']) && is_ipaddr($gateways->getAddress($pconfig['gateway']))) {
+        if ($pconfig['ipprotocol'] == "inet6" && !is_ipaddrv6($gateways->getAddress($pconfig['gateway']))) {
             $input_errors[] = gettext('You can not assign the IPv4 Gateway to an IPv6 filter rule.');
         }
-        if ($pconfig['ipprotocol'] == "inet" && !is_ipaddrv4(lookup_gateway_ip_by_name($pconfig['gateway']))) {
+        if ($pconfig['ipprotocol'] == "inet" && !is_ipaddrv4($gateways->getAddress($pconfig['gateway']))) {
             $input_errors[] = gettext('You can not assign the IPv6 Gateway to an IPv4 filter rule.');
         }
     }