diff --git a/addons/calendar/models/calendar_event.py b/addons/calendar/models/calendar_event.py
index fdc52eff4e4..e4123fa054f 100644
--- a/addons/calendar/models/calendar_event.py
+++ b/addons/calendar/models/calendar_event.py
@@ -789,6 +789,11 @@ class Meeting(models.Model):
 
         removed_partner_ids = []
         added_partner_ids = []
+
+        # if commands are just integers, assume they are ids with the intent to `Command.set`
+        if partner_commands and isinstance(partner_commands[0], int):
+            partner_commands = [Command.set(partner_commands)]
+
         for command in partner_commands:
             op = command[0]
             if op in (2, 3, Command.delete, Command.unlink):  # Remove partner
diff --git a/addons/calendar/tests/test_attendees.py b/addons/calendar/tests/test_attendees.py
index 629a7d5556e..98e9206483b 100644
--- a/addons/calendar/tests/test_attendees.py
+++ b/addons/calendar/tests/test_attendees.py
@@ -68,6 +68,11 @@ class TestEventNotifications(TransactionCase):
         events.partner_ids = self.partner
         self.assertEqual(len(events.attendee_ids), 2, "It should have created one attendee per event")
 
+    def test_attendee_added_write(self):
+        """Test that writing ids directly on partner_ids instead of commands is handled."""
+        self.event.write({'partner_ids': [self.partner.id]})
+        self.assertEqual(self.event.attendee_ids.partner_id, self.partner, "It should be linked to the partner")
+
     def test_existing_attendee_added(self):
         self.event.partner_ids = self.partner
         attendee = self.event.attendee_ids