diff --git a/examples/platforms/simulation/ble.c b/examples/platforms/simulation/ble.c
index 7a57c5284..aeaa1d7ef 100644
--- a/examples/platforms/simulation/ble.c
+++ b/examples/platforms/simulation/ble.c
@@ -256,8 +256,13 @@ void platformBleProcess(otInstance *aInstance, const fd_set *aReadFdSet, const f
         }
         else if (rval == 0)
         {
-            // socket is closed, which should not happen
-            assert(false);
+            // A zero-length datagram: simulates Commissioner suddenly disconnected the BLE link.
+            if (sIsConnected)
+            {
+                sIsConnected = false;
+                otLogDebgPlat("BLE client link disconnected");
+                otPlatBleGapOnDisconnected(aInstance, 0);
+            }
         }
         else if (errno != EINTR && errno != EAGAIN)
         {
diff --git a/tools/tcat_ble_client/ble/udp_stream.py b/tools/tcat_ble_client/ble/udp_stream.py
index 2d3b980a0..7f1edf742 100644
--- a/tools/tcat_ble_client/ble/udp_stream.py
+++ b/tools/tcat_ble_client/ble/udp_stream.py
@@ -60,6 +60,11 @@ class UdpStream:
         else:
             return b''
 
+    async def simulation_ble_disconnect(self):
+        # Simulate a BLE link break (e.g. peer out of range) by sending a zero-length UDP
+        # datagram. Unlike `disconnect`, this does not send a Disconnect TLV and does not
+        # perform a clean TLS shutdown.
+        self.socket.sendto(b'', self.address)
+
     async def disconnect(self):
-        if self.socket is not None:
-            self.socket.close()
+        self.socket.close()
diff --git a/tools/tcat_ble_client/cli/base_commands.py b/tools/tcat_ble_client/cli/base_commands.py
index c466d7a64..1bdad9cdd 100644
--- a/tools/tcat_ble_client/cli/base_commands.py
+++ b/tools/tcat_ble_client/cli/base_commands.py
@@ -244,6 +244,27 @@ class DisconnectCommand(Command):
         return CommandResultNone()
 
 
+class SimulationBleDisconnectCommand(Command):
+
+    def get_help_string(self) -> str:
+        return 'Simulate a BLE link break to a simulated TCAT device (no Disconnect TLV, no TLS shutdown).'
+
+    async def execute_default(self, args, context) -> CommandResult:
+        ble_stream = context['ble_stream']
+        if not isinstance(ble_stream, UdpStream):
+            return CommandResultError('only available for a simulation connection (use \'simulation <id>\' first).')
+
+        print('Disconnecting simulated BLE link...')
+        # Signal the abrupt link break to the device, then drop local stream state without a TLS
+        # shutdown (no close-notify), mirroring a real abrupt disconnect on the client side too.
+        await ble_stream.simulation_ble_disconnect()
+        await ble_stream.disconnect()
+        context['ble_stream'] = None
+        context['ble_sstream'] = None
+        print('Done')
+        return CommandResultNone()
+
+
 class ExtractDatasetCommand(BleCommand):
 
     def get_log_string(self) -> str:
diff --git a/tools/tcat_ble_client/cli/cli.py b/tools/tcat_ble_client/cli/cli.py
index 25fc6a0a3..dfc1c8354 100644
--- a/tools/tcat_ble_client/cli/cli.py
+++ b/tools/tcat_ble_client/cli/cli.py
@@ -38,7 +38,7 @@ from cli.base_commands import (DisconnectCommand, HelpCommand, HelloCommand, Com
                                GetRandomNumberChallenge, ThreadStateCommand, ScanCommand, PresentHash,
                                DiagnosticTlvsCommand, GetApplicationLayersCommand, SendVendorData,
                                SendApplicationData1, SendApplicationData2, SendApplicationData3, SendApplicationData4,
-                               SimulationCommand, connect_helper, disconnect_helper)
+                               SimulationCommand, SimulationBleDisconnectCommand, connect_helper, disconnect_helper)
 from .command import CommandResultNone, CommandResult
 from .tlv_commands import TlvCommand
 from cli.dataset_commands import (DatasetCommand)
@@ -72,6 +72,7 @@ class CLI:
             'thread': ThreadStateCommand(),
             'scan': ScanCommand(),
             'simulation': SimulationCommand(),
+            'simulation_ble_disconnect': SimulationBleDisconnectCommand(),
             'random_challenge': GetRandomNumberChallenge(),
             'present_hash': PresentHash(),
             'tlv': TlvCommand(),