diff --git a/include/netlink/route/link/ip6tnl.h b/include/netlink/route/link/ip6tnl.h
index 7e0c295..4021356 100644
--- a/include/netlink/route/link/ip6tnl.h
+++ b/include/netlink/route/link/ip6tnl.h
@@ -22,6 +22,8 @@ extern "C" {
 	extern struct rtnl_link *rtnl_link_ip6_tnl_alloc(void);
 	extern int rtnl_link_ip6_tnl_add(struct nl_sock *sk, const char *name);
 
+	extern int rtnl_link_is_ip6_tnl(struct rtnl_link *link);
+
 	extern int rtnl_link_ip6_tnl_set_link(struct rtnl_link *link,  uint32_t index);
 	extern uint32_t rtnl_link_ip6_tnl_get_link(struct rtnl_link *link);