Trump said Britain should refuse to pay its 39 billion pound ($49bn) EU divorce bill and “walk away” from Brexit talks if Brussels does not give the UK what it wants, he told the UK’s Sunday Times newspaper.
The intervention comes after Trump used another newspaper interview to declare that former foreign minister Boris Johnson would be an “excellent” replacement for May.
The US president begins a state visit to Britain on Monday that starts with a private lunch with Queen Elizabeth II and a state banquet at Buckingham Palace.
But large protests are also planned over what London Mayor Sadiq Khan described as Trump’s “divisive behaviour”, and opposition politicians are boycotting the banquet.
‘I wouldn’t pay’
Trump embarrassed May with outspoken remarks on Brexit during his visit to Britain last year. On Sunday he again urged the next government to follow his own negotiating rule-book.
“If they don’t get what they want, I would walk away… If you don’t get the deal you want, if you don’t get a fair deal, then you walk away,” he said in the article.
May has already agreed to pay to cover Britain’s liabilities as it moves to sever four decades of EU membership.
But Trump said: “If I were them I wouldn’t pay $50 billion. That is me. I would not pay, that is a tremendous number.”
May agreed on a divorce deal with Brussels last November, but British MPs have rejected it three times and she has had to delay Brexit twice.
She has now been forced out and her Conservative party is beginning the process of finding a new leader, with 13 candidates already declared.
Johnson, one of the frontrunners, is among several to say Britain should leave the EU on October 31 with or without a deal.
They are under pressure from the Brexit party, the latest political vehicle of anti-EU populist leader Nigel Farage, which gained the most UK seats in European Parliament elections last month.
Trump said he believed Farage should play a role in negotiating Brexit with the European Union, saying he had a “lot to offer”.
Britain’s future trading relationship with the United States will be crucial to its post-Brexit success and likely discussed during Trump’s talks with May at Downing Street this week.
But some fear Britain would be steamrolled by the far bigger US into accepting an unbalanced accord, especially given Trump’s “America First” stance that is shaking up trade ties with Mexico, Canada, Japan and China.
US Ambassador to Britain Woody Johnson told BBC television that Washington was already preparing the way for a trade deal and it would be done “as expeditiously as any agreement we’ve ever had”.
He said he would expect Britain to be open to US agricultural products, and when asked about access of US firms to Britain’s cherished state-run health service, said “all things that are traded would be on the table”.
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