Donald Trump doesn’t hold much back - even if that means making life very hard for one of the United States’ closest allies.

Mr Trump waded into UK Prime Minister Theresa May’s Brexit nightmare when he declared her proposed withdrawal agreement with the European Union sounded like “a good deal for the EU”.

“I think we have to take a look at seriously whether or not the UK is allowed to trade. Because you know, right now, if you look at the deal, they may not be able to trade with us and that wouldn’t be a good thing,” Mr Trump said on the White House’s South Lawn.

He appeared to suggest Mrs May’s deal was flawed - and that she was aware of it.

“I don’t think they meant that. I don’t think that the Prime Minister meant that. And hopefully, she’ll be able to do something about that,” the President said.

“But right now, as the deal stands, they may not be able to trade with the US and I don’t think they want that at all - that would be a very negative for the deal.

Mrs May hit back today, saying President Trump had got the wrong end of the stick on her deal.

“It clearly identifies we will have an independent trade policy and we will be able to negotiate trade deals with countries around the rest of the world.

She went on to say: “As regards the United States, we have already been talking to them about the sort of agreement that we could have in the future.

“We have a working group set up and that is working very well, has met several times and is continuing to work with the US on this.”

Mr Trump once said his support for Britain leaving the EU was so great he was known as “Mr Brexit”. But in recent months he has been a thorn in Mrs May’s side, even casting doubt on her negotiation skills in a bombshell News Corp interview in July hours before he was due to meet her face-to-face.

“I would have done it much differently. I actually told Theresa May how to do it but she didn’t agree, she didn’t listen to me.

“She wanted to go a different route.

“I would actually say that she probably went the opposite way. And that is fine.

“She should negotiate the best way she knows how. But it is too bad what is going on.”

The EU has voted to accept the deal and now British MPs will have their say on December 11 in a “meaningful vote” that will radically alter British politics one way or the other.

Either MPs support the deal and the passage of Brexit bills through the House of Commons or they vote it down which would risk Mrs May’s position as prime minister and throw Brexit into chaos.

It would drastically increase the chance of leaving the EU next March with no deal in place, something that risks severe disruption in the short term at least. The level of disruption and the likely impact it will have is contested - some believe it will be fleeting, while many others worry it will be a serious shock for the economy that will have lasting effect and impact directly on the British public.

EU leaders have warned there is no room for renegotiating the deal - either by Mrs May or a successor - so the vote is seen as a crucial test of how far pro-Brexit MPs are willing to push in their bid for a “hard” exit from the EU.

Meanwhile, Mrs May is facing continuing calls for her to resign, with wavering Conservative MPs asking her to set a date for her departure to win their support in the Brexit vote.

The Prime Minister is under pressure from her Cabinet to say when she will go as she fights to get her agreement through parliament - as another MP announced he had submitted a letter of no-confidence in her.

A confidence vote is triggered if there are 48 letters.

Cabinet sources told The Times that a promise from Mrs May to quit after Brexit day on March 29 would help get her deal through the Commons.

They think whoever replaces her could then fight for a better trade deal in future.

One told the paper: “We know that the future relationship is not binding. This means she is the problem, not the deal per se, since it leaves plenty of flexibility for a successor to organise technical solutions for the Irish border and move towards Canada (style deal).”

Mrs May has pushed on with trying to sell her plan to the public and is preparing a nationwide blitz with visits today to Wales and Belfast. She is also taking on Labour leader Jeremy Corbyn in a televised debate on Sunday night

She wants to expose what she insists is the Opposition Leader’s failure to offer any workable alternative to hers for leaving the EU.

The prime time TV clash would mark the end of Mrs May’s epic two week fight to win MPs support and set her up for what will be the biggest week of her political life - and one that could make or break her premiership.

andrew.koubaridis@news.com.au