diff --git a/backend/open_webui/utils/timers.py b/backend/open_webui/utils/timers.py
index d8be899dff..15a6b898db 100644
--- a/backend/open_webui/utils/timers.py
+++ b/backend/open_webui/utils/timers.py
@@ -11,7 +11,7 @@ from datetime import datetime, timezone
 from typing import Literal
 from uuid import uuid4
 
-from fastapi import Request
+from fastapi import HTTPException, Request
 from open_webui.internal.db import get_async_db
 from open_webui.models.chat_messages import ChatMessages
 from open_webui.models.chats import Chat, ChatForm, Chats
@@ -416,7 +416,20 @@ async def execute_due_timer(app, timer_id: str, claim_id: str | None = None) ->
             await app.state.CHAT_COMPLETION_HANDLER(request, form_data, user=user)
         except Exception as exc:
             log.exception(f'Timer {timer_id} completion failed')
-            await _set_timer_state(timer_id, 'error', timer_error=str(exc)[:500])
+            error_detail = exc.detail if isinstance(exc, HTTPException) else str(exc)
+            await _set_timer_state(timer_id, 'error', timer_error=error_detail[:500])
+            await Chats.upsert_message_to_chat_by_id_and_message_id(
+                parent_chat_id, assistant_message_id, {'error': {'content': error_detail}, 'done': True}
+            )
+            await sio.emit(
+                'events',
+                {
+                    'chat_id': parent_chat_id,
+                    'message_id': assistant_message_id,
+                    'data': {'type': 'chat:message:error', 'data': {'error': {'content': error_detail}, 'done': True}},
+                },
+                room=f'user:{timer.user_id}',
+            )
 
 
 async def _set_timer_state(timer_id: str, status: str, **fields) -> None: