Maybe a nicely worded letter from Boris to that nice Mr Macaroni in France isn't such a bad idea.
Something along the lines of mentioning our good relationships over the years - well apart from a few hiccups in the middle ages - and helpfully pointing out that WW2 ended quite a while ago, and there really is no need to recreate the Dunkirk evacuations using rubber dinghy's and migrants. Oh and while we're at it, your cheese stinks
That should do it
Actually, it may be better if that Pretty Pratty woman sent it