diff --git a/client/ayon_core/tools/tray/lib.py b/client/ayon_core/tools/tray/lib.py
index c26f4835b1..ad190482a8 100644
--- a/client/ayon_core/tools/tray/lib.py
+++ b/client/ayon_core/tools/tray/lib.py
@@ -356,6 +356,39 @@ def is_tray_running(
     return state != TrayState.NOT_RUNNING
 
 
+def show_message_in_tray(
+    title, message, icon=None, msecs=None, tray_url=None
+):
+    """Show message in tray.
+
+    Args:
+        title (str): Message title.
+        message (str): Message content.
+        icon (Optional[Literal["information", "warning", "critical"]]): Icon
+            for the message.
+        msecs (Optional[int]): Duration of the message.
+        tray_url (Optional[str]): Tray server url.
+
+    """
+    if not tray_url:
+        tray_url = get_tray_server_url()
+
+    # TODO handle this case, e.g. raise an error?
+    if not tray_url:
+        return
+
+    # TODO handle response, can fail whole request or can fail on status
+    requests.post(
+        f"{tray_url}/tray/message",
+        json={
+            "title": title,
+            "message": message,
+            "icon": icon,
+            "msecs": msecs
+        }
+    )
+
+
 def make_sure_tray_is_running(
     ayon_url: Optional[str] = None,
     variant: Optional[str] = None,
@@ -412,6 +445,10 @@ def main(force=False):
         state = TrayState.NOT_RUNNING
 
     if state == TrayState.RUNNING:
+        show_message_in_tray(
+            "Tray is already running",
+            "Your AYON tray application is already running."
+        )
         print("Tray is already running.")
         return
 
diff --git a/client/ayon_core/tools/tray/ui/tray.py b/client/ayon_core/tools/tray/ui/tray.py
index 60c0a63cdb..f6a8add861 100644
--- a/client/ayon_core/tools/tray/ui/tray.py
+++ b/client/ayon_core/tools/tray/ui/tray.py
@@ -136,6 +136,7 @@ class TrayManager:
             kwargs["msecs"] = msecs
 
         self.tray_widget.showMessage(*args, **kwargs)
+        # TODO validate 'self.tray_widget.supportsMessages()'
 
     def initialize_addons(self):
         """Add addons to tray."""
@@ -148,6 +149,9 @@ class TrayManager:
         self._addons_manager.add_route(
             "GET", "/tray", self._web_get_tray_info
         )
+        self._addons_manager.add_route(
+            "POST", "/tray/message", self._web_show_tray_message
+        )
 
         admin_submenu = ITrayAction.admin_submenu(tray_menu)
         tray_menu.addMenu(admin_submenu)
@@ -294,6 +298,36 @@ class TrayManager:
             "running_time": time.time() - self._start_time,
         })
 
+    async def _web_show_tray_message(self, request: Request) -> Response:
+        data = await request.json()
+        try:
+            title = data["title"]
+            message = data["message"]
+            icon = data.get("icon")
+            msecs = data.get("msecs")
+        except KeyError as exc:
+            return json_response(
+                {
+                    "error": f"Missing required data. {exc}",
+                    "success": False,
+                },
+                status=400,
+            )
+
+        if icon == "information":
+            icon = QtWidgets.QSystemTrayIconInformation
+        elif icon == "warning":
+            icon = QtWidgets.QSystemTrayIconWarning
+        elif icon == "critical":
+            icon = QtWidgets.QSystemTrayIcon.Critical
+        else:
+            icon = None
+
+        self.execute_in_main_thread(
+            self.show_tray_message, title, message, icon, msecs
+        )
+        return json_response({"success": True})
+
     def _on_update_check_timer(self):
         try:
             bundles = ayon_api.get_bundles()