diff --git a/ipsec/ovs-monitor-ipsec.in b/ipsec/ovs-monitor-ipsec.in
index b72d562c784..f9451e53cd4 100755
--- a/ipsec/ovs-monitor-ipsec.in
+++ b/ipsec/ovs-monitor-ipsec.in
@@ -625,7 +625,10 @@ conn prevent_unencrypted_vxlan
                 continue
 
             conn = m.group(1)
-            m = re.match(r"(.*)(-in-\d+|-out-\d+|-\d+)", conn)
+            m = re.match(r"(.*)(-in-\d+|-out-\d+)", conn)
+            if not m:
+                # GRE connections have format <iface>-<ver>
+                m = re.match(r"(.*)(-\d+)", conn)
             if not m:
                 continue