It's worth parsing what Trump said about the UK-US trade deal and Brexit. Contrary to the Sun front-page headline, I don't think he declared "the deal is off" or made an ultimatum over it. Here's what he said: 
My read is that he's saying that May's plan would result in continued close links between the UK and EU, so he'd have to deal with the EU in these negotiations, and he doesn't get along with the EU on trade, so this kind of Brexit would probably kill the chances of a deal.
In other words, I think he was musing about what is evidently new info for him on the Brexit situation, and complaining about the EU, not making a dramatic threat, which is how The Sun, being The Sun, framed it. /End
That's what *I'm* saying, basically: The Sun is framing the trade comments as a dramatic policy statement when it sounds like Trump was merely talking as he talks.
