Peter Black makes an obvious point:
[D]espite the bravado by the UK Government that they will not pay a leaving fee they know that if they want to secure a trade deal with the single market then that is precisely what they will have to do.
I keep on seeing articles in which various groups of people try to make some legalistic argument or other about the UK not paying the balance of its debts, and this is the thought that keeps leaping out at me. You can’t go into negotiations having already poisoned the atmosphere — as the Tories are increasingly doing — and then expect a decent deal at the end of it.