diff --git a/ggsn/ggsn.c b/ggsn/ggsn.c
index 6306924..9b45109 100644
--- a/ggsn/ggsn.c
+++ b/ggsn/ggsn.c
@@ -1022,6 +1022,7 @@
 
 	/* Start GTP re-transmission timer */
 	osmo_timer_setup(&ggsn->gtp_timer, ggsn_gtp_tmr_cb, ggsn);
+	ggsn_gtp_tmr_start(ggsn);
 
 	gtp_set_cb_data_ind(ggsn->gsn, encaps_tun);
 	gtp_set_cb_delete_context(ggsn->gsn, delete_context);