diff --git a/subsys/bluetooth/controller/ll_sw/nordic/lll/lll_master.c b/subsys/bluetooth/controller/ll_sw/nordic/lll/lll_master.c
index 14a6c84847e..61856b9772d 100644
--- a/subsys/bluetooth/controller/ll_sw/nordic/lll/lll_master.c
+++ b/subsys/bluetooth/controller/ll_sw/nordic/lll/lll_master.c
@@ -120,6 +120,7 @@ static int prepare_cb(struct lll_prepare_param *prepare_param)
 					       &lll->data_chan_map[0],
 					       lll->data_chan_count);
 #else /* !CONFIG_BT_CTLR_CHAN_SEL_2 */
+		data_chan_use = 0;
 		LL_ASSERT(0);
 #endif /* !CONFIG_BT_CTLR_CHAN_SEL_2 */
 	} else {
diff --git a/subsys/bluetooth/controller/ll_sw/nordic/lll/lll_slave.c b/subsys/bluetooth/controller/ll_sw/nordic/lll/lll_slave.c
index f4c260a46a2..461395257bb 100644
--- a/subsys/bluetooth/controller/ll_sw/nordic/lll/lll_slave.c
+++ b/subsys/bluetooth/controller/ll_sw/nordic/lll/lll_slave.c
@@ -131,6 +131,7 @@ static int prepare_cb(struct lll_prepare_param *prepare_param)
 					       &lll->data_chan_map[0],
 					       lll->data_chan_count);
 #else /* !CONFIG_BT_CTLR_CHAN_SEL_2 */
+		data_chan_use = 0;
 		LL_ASSERT(0);
 #endif /* !CONFIG_BT_CTLR_CHAN_SEL_2 */
 	} else {