diff --git a/openair2/COMMON/f1ap_messages_types.h b/openair2/COMMON/f1ap_messages_types.h
index f357fae2d8..569f3857c0 100644
--- a/openair2/COMMON/f1ap_messages_types.h
+++ b/openair2/COMMON/f1ap_messages_types.h
@@ -466,6 +466,11 @@ typedef enum ReconfigurationCompl_e {
   RRCreconf_success          = 2,
 } ReconfigurationCompl_t;
 
+typedef enum TransmActionInd_e {
+  TransmActionInd_STOP,
+  TransmActionInd_RESTART,
+} TransmActionInd_t;
+
 typedef struct f1ap_ue_context_setup_s {
   uint32_t gNB_CU_ue_id;
   uint32_t gNB_DU_ue_id;
@@ -496,6 +501,7 @@ typedef struct f1ap_ue_context_setup_s {
   ReconfigurationCompl_t ReconfigComplOutcome;
   uint8_t *rrc_container;
   int      rrc_container_length;
+  TransmActionInd_t *transm_action_ind;
 } f1ap_ue_context_setup_t, f1ap_ue_context_modif_req_t, f1ap_ue_context_modif_resp_t;
 
 typedef enum F1ap_Cause_e {
diff --git a/openair2/F1AP/f1ap_cu_ue_context_management.c b/openair2/F1AP/f1ap_cu_ue_context_management.c
index ca6c939a3a..924c9ecfca 100644
--- a/openair2/F1AP/f1ap_cu_ue_context_management.c
+++ b/openair2/F1AP/f1ap_cu_ue_context_management.c
@@ -1023,12 +1023,15 @@ int CU_send_UE_CONTEXT_MODIFICATION_REQUEST(sctp_assoc_t assoc_id, f1ap_ue_conte
 
   /* optional */
   /* c7. TransmissionActionIndicator */
-  if (0) {
+  if (f1ap_ue_context_modification_req->transm_action_ind != NULL) {
     asn1cSequenceAdd(out->protocolIEs.list, F1AP_UEContextModificationRequestIEs_t, ie7);
     ie7->id                                     = F1AP_ProtocolIE_ID_id_TransmissionActionIndicator;
     ie7->criticality                            = F1AP_Criticality_ignore;
     ie7->value.present                          = F1AP_UEContextModificationRequestIEs__value_PR_TransmissionActionIndicator;
-    ie7->value.choice.TransmissionActionIndicator = F1AP_TransmissionActionIndicator_stop;
+    ie7->value.choice.TransmissionActionIndicator = *f1ap_ue_context_modification_req->transm_action_ind;
+    // Stop is guaranteed to be 0, by restart might be different from 1
+    static_assert((int)F1AP_TransmissionActionIndicator_restart == (int)TransmActionInd_RESTART,
+                  "mismatch of ASN.1 and internal representation\n");
   }
 
   /* optional */
diff --git a/openair2/F1AP/f1ap_du_ue_context_management.c b/openair2/F1AP/f1ap_du_ue_context_management.c
index 8844e79baf..18a04962ad 100644
--- a/openair2/F1AP/f1ap_du_ue_context_management.c
+++ b/openair2/F1AP/f1ap_du_ue_context_management.c
@@ -911,6 +911,21 @@ int DU_handle_UE_CONTEXT_MODIFICATION_REQUEST(instance_t instance, sctp_assoc_t
   F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_UEContextModificationRequestIEs_t, ieSrb, container,
       F1AP_ProtocolIE_ID_id_SRBs_ToBeSetupMod_List, false);
 
+  F1AP_UEContextModificationRequestIEs_t *ieTxInd;
+  F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_UEContextModificationRequestIEs_t,
+                             ieTxInd,
+                             container,
+                             F1AP_ProtocolIE_ID_id_TransmissionActionIndicator,
+                             false);
+
+  if (ieTxInd != NULL) {
+    f1ap_ue_context_modification_req->transm_action_ind = calloc_or_fail(1, sizeof(*f1ap_ue_context_modification_req->transm_action_ind));
+    *f1ap_ue_context_modification_req->transm_action_ind = ieTxInd->value.choice.TransmissionActionIndicator;
+    // Stop is guaranteed to be 0, by restart might be different from 1
+    static_assert((int)F1AP_TransmissionActionIndicator_restart == (int)TransmActionInd_RESTART,
+                  "mismatch of ASN.1 and internal representation\n");
+  }
+
   if(ieSrb != NULL) {
     f1ap_ue_context_modification_req->srbs_to_be_setup_length = ieSrb->value.choice.SRBs_ToBeSetupMod_List.list.count;
     f1ap_ue_context_modification_req->srbs_to_be_setup = calloc(f1ap_ue_context_modification_req->srbs_to_be_setup_length,
diff --git a/openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_primitives.c b/openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_primitives.c
index d860ec49bd..5ae2eb8607 100644
--- a/openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_primitives.c
+++ b/openair2/LAYER2/NR_MAC_gNB/gNB_scheduler_primitives.c
@@ -3017,6 +3017,14 @@ int nr_mac_interrupt_ue_transmission(gNB_MAC_INST *mac, NR_UE_info_t *UE, interr
   return 0;
 }
 
+int nr_transmission_action_indicator_stop(gNB_MAC_INST *mac, NR_UE_info_t *UE_info)
+{
+  int delay = nr_mac_get_reconfig_delay_slots(UE_info->current_DL_BWP.scs);
+  nr_mac_interrupt_ue_transmission(mac, UE_info, FOLLOW_OUTOFSYNC, delay);
+  LOG_I(NR_MAC, "gNB-DU received the TransmissionActionIndicator with Stop value for UE %04x\n", UE_info->rnti);
+  return 0;
+}
+
 void nr_mac_trigger_release_complete(gNB_MAC_INST *mac, int rnti)
 {
   // the CU might not know such UE, e.g., because we never sent a message to
@@ -3078,7 +3086,10 @@ void nr_mac_update_timers(module_id_t module_id,
     if (nr_timer_tick(&sched_ctrl->transm_interrupt)) {
       /* expired */
       nr_timer_stop(&sched_ctrl->transm_interrupt);
-      nr_mac_apply_cellgroup(mac, UE, frame, slot);
+      if (UE->interrupt_action == FOLLOW_OUTOFSYNC)
+        nr_mac_trigger_ul_failure(sched_ctrl, UE->current_DL_BWP.scs);
+      else
+        nr_mac_apply_cellgroup(mac, UE, frame, slot);
     }
   }
 }
diff --git a/openair2/LAYER2/NR_MAC_gNB/mac_proto.h b/openair2/LAYER2/NR_MAC_gNB/mac_proto.h
index e63bbd8f99..4ee100f812 100644
--- a/openair2/LAYER2/NR_MAC_gNB/mac_proto.h
+++ b/openair2/LAYER2/NR_MAC_gNB/mac_proto.h
@@ -57,6 +57,7 @@ int nr_mac_get_reconfig_delay_slots(NR_SubcarrierSpacing_t scs);
 
 bool nr_mac_prepare_cellgroup_update(gNB_MAC_INST *nrmac, NR_UE_info_t *UE, NR_CellGroupConfig_t *CellGroup);
 int nr_mac_interrupt_ue_transmission(gNB_MAC_INST *mac, NR_UE_info_t *UE, interrupt_followup_action_t action, int slots);
+int nr_transmission_action_indicator_stop(gNB_MAC_INST *mac, NR_UE_info_t *UE_info);
 
 void clear_nr_nfapi_information(gNB_MAC_INST *gNB,
                                 int CC_idP,
diff --git a/openair2/LAYER2/NR_MAC_gNB/mac_rrc_dl_handler.c b/openair2/LAYER2/NR_MAC_gNB/mac_rrc_dl_handler.c
index 33c0d5e33e..a69ab2732e 100644
--- a/openair2/LAYER2/NR_MAC_gNB/mac_rrc_dl_handler.c
+++ b/openair2/LAYER2/NR_MAC_gNB/mac_rrc_dl_handler.c
@@ -588,6 +588,11 @@ void ue_context_modification_request(const f1ap_ue_context_modif_req_t *req)
   } else {
     ASN_STRUCT_FREE(asn_DEF_NR_CellGroupConfig, new_CellGroup); // we actually don't need it
   }
+
+  if (req->transm_action_ind != NULL) {
+    AssertFatal(*req->transm_action_ind == TransmActionInd_STOP, "Transmission Action Indicator restart not handled yet\n");
+    nr_transmission_action_indicator_stop(mac, UE);
+  }
   NR_SCHED_UNLOCK(&mac->sched_lock);
 
   /* some sanity checks, since we use the same type for request and response */
diff --git a/openair2/LAYER2/NR_MAC_gNB/nr_mac_gNB.h b/openair2/LAYER2/NR_MAC_gNB/nr_mac_gNB.h
index 8d97ddc607..e0cf53c5a0 100644
--- a/openair2/LAYER2/NR_MAC_gNB/nr_mac_gNB.h
+++ b/openair2/LAYER2/NR_MAC_gNB/nr_mac_gNB.h
@@ -739,7 +739,7 @@ typedef struct nr_mac_rrc_ul_if_s {
   initial_ul_rrc_message_transfer_func_t initial_ul_rrc_message_transfer;
 } nr_mac_rrc_ul_if_t;
 
-typedef enum interrupt_followup_action { FOLLOW_INSYNC, FOLLOW_INSYNC_RECONFIG } interrupt_followup_action_t;
+typedef enum interrupt_followup_action { FOLLOW_INSYNC, FOLLOW_INSYNC_RECONFIG, FOLLOW_OUTOFSYNC  } interrupt_followup_action_t;
 
 /*! \brief UE list used by gNB to order UEs/CC for scheduling*/
 typedef struct {
diff --git a/openair2/RRC/NR/mac_rrc_dl_f1ap.c b/openair2/RRC/NR/mac_rrc_dl_f1ap.c
index a802e7ab4d..70d36a144f 100644
--- a/openair2/RRC/NR/mac_rrc_dl_f1ap.c
+++ b/openair2/RRC/NR/mac_rrc_dl_f1ap.c
@@ -168,6 +168,11 @@ static void ue_context_modification_request_f1ap(sctp_assoc_t assoc_id, const f1
     f1ap_msg->rrc_container_length = req->rrc_container_length;
     memcpy(f1ap_msg->rrc_container, req->rrc_container, req->rrc_container_length);
   }
+  if (req->transm_action_ind != NULL) {
+    f1ap_msg->transm_action_ind = malloc(sizeof *f1ap_msg->transm_action_ind);
+    AssertFatal(f1ap_msg->transm_action_ind != NULL, "out of memory\n");
+    *f1ap_msg->transm_action_ind = *req->transm_action_ind;
+  }
   itti_send_msg_to_task(TASK_CU_F1, 0, msg);
 }