diff --git a/src/libcharon/kernel/kernel_ipsec.h b/src/libcharon/kernel/kernel_ipsec.h
index 6663d730b..3ef5811d9 100644
--- a/src/libcharon/kernel/kernel_ipsec.h
+++ b/src/libcharon/kernel/kernel_ipsec.h
@@ -113,6 +113,8 @@ struct kernel_ipsec_add_sa_t {
 	bool copy_ecn;
 	/** Whether to copy the DSCP header field to/from the outer header */
 	dscp_copy_t copy_dscp;
+	/** TRUE if the peer doesn't support receiving fragments in AGGFRAG pkts */
+	bool iptfs_dont_frag;
 	/** TRUE if initiator of the exchange creating the SA */
 	bool initiator;
 	/** TRUE if this is an inbound SA */