diff --git a/mistral/engine/engine_server.py b/mistral/engine/engine_server.py
index 7c3d5cdf1..e44921b5c 100644
--- a/mistral/engine/engine_server.py
+++ b/mistral/engine/engine_server.py
@@ -132,10 +132,6 @@ class EngineServer(service_base.MistralService):
             **params
         )
 
-    def on_task_state_change(self, rpc_ctx, task_ex_id, state,
-                             state_info=None):
-        return self.engine.on_task_state_change(task_ex_id, state, state_info)
-
     def on_action_complete(self, rpc_ctx, action_ex_id, result_data,
                            result_error, wf_action):
         """Receives RPC calls to communicate action result to engine.
diff --git a/mistral/engine/rpc_backend/rpc.py b/mistral/engine/rpc_backend/rpc.py
index 4816ee172..4a8112ab2 100644
--- a/mistral/engine/rpc_backend/rpc.py
+++ b/mistral/engine/rpc_backend/rpc.py
@@ -198,15 +198,6 @@ class EngineClient(base.Engine):
             params=params
         )
 
-    def on_task_state_change(self, task_ex_id, state, state_info=None):
-        return self._client.sync_call(
-            auth_ctx.ctx(),
-            'on_task_state_change',
-            task_ex_id=task_ex_id,
-            state=state,
-            state_info=state_info
-        )
-
     @wrap_messaging_exception
     def on_action_complete(self, action_ex_id, result, wf_action=False,
                            async=False):