diff --git a/src/gprs_bssgp_pcu.h b/src/gprs_bssgp_pcu.h
index e8ae1a9..f98e719 100644
--- a/src/gprs_bssgp_pcu.h
+++ b/src/gprs_bssgp_pcu.h
@@ -80,6 +80,9 @@
 		uint16_t nsvci, uint16_t bvci, uint16_t mcc, uint16_t mnc, bool mnc_3_digits,
 		uint16_t lac, uint16_t rac, uint16_t cell_id);
 
+int gprs_bssgp_ns_cb(enum gprs_ns_evt event, struct gprs_nsvc *nsvc,
+	       struct msgb *msg, uint16_t bvci);
+
 void gprs_bssgp_destroy(void);
 
 struct bssgp_bvc_ctx *gprs_bssgp_pcu_current_bctx(void);