diff --git a/src/libcharon/plugins/osmo_epdg/osmo_epdg_utils.c b/src/libcharon/plugins/osmo_epdg/osmo_epdg_utils.c
index 1ca34ed96..5898505ef 100644
--- a/src/libcharon/plugins/osmo_epdg/osmo_epdg_utils.c
+++ b/src/libcharon/plugins/osmo_epdg/osmo_epdg_utils.c
@@ -43,6 +43,17 @@ struct msgb *chunk_to_msgb(chunk_t *chunk)
 	return msg;
 }
 
+int get_imsi_ike(ike_sa_t *ike_sa, char *imsi, size_t imsi_len)
+{
+	identification_t *imsi_id = ike_sa->get_other_id(ike_sa);
+	if (!imsi_id)
+	{
+		return -1;
+	}
+
+	return get_imsi(imsi_id, imsi, imsi_len);
+}
+
 int get_imsi(identification_t *id, char *imsi, size_t imsi_len)
 {
 	chunk_t nai = id->get_encoding(id);
diff --git a/src/libcharon/plugins/osmo_epdg/osmo_epdg_utils.h b/src/libcharon/plugins/osmo_epdg/osmo_epdg_utils.h
index 713fd1dde..3a8ac3978 100644
--- a/src/libcharon/plugins/osmo_epdg/osmo_epdg_utils.h
+++ b/src/libcharon/plugins/osmo_epdg/osmo_epdg_utils.h
@@ -58,6 +58,7 @@ typedef struct osmo_epdg_ue osmo_epdg_ue_t;
 
 struct msgb *chunk_to_msgb(chunk_t *chunk);
 int get_imsi(identification_t *id, char *imsi, size_t imsi_len);
+int get_imsi_ike(ike_sa_t *ike_sa, char *imsi, size_t imsi_len);
 int get_apn(ike_sa_t *sa, char *apn, size_t apn_len);
 
 #endif /* OSMO_EPDG_UTILS_H_ */