Downing Street was forced to hit back overnight at the claims, saying the UK would be able to strike independent trade agreements under the prime minister’s plan as the country would have left the customs union – which prevents EU countries from trading independently.
And cabinet minister Robert Jenrick also disagreed with the US president, telling the Today programme that the president’s view was “not how we see it”.
Post-Brexit trade with the US is prized by Eurosceptics as a major benefit of leaving the EU, despite concerns in some quarters that the UK would be forced to water down food standards to secure a deal.
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Mr Trump, who is an admirer of the prime minister, suggested that a deal would be off the table in an LBC interview with the Brexit Party leader.
The president said: “We want to do trade with the UK, and they want to do trade with us.
“And to be honest with you, this deal, under certain aspects of the deal – you can’t do it, you can’t do it, you can’t trade. We can’t make a trade deal with the UK.”
His comments came as a blow to the prime minister at the start of a gruelling election campaign, which will be fought on Mr Johnson’s ability to deliver on Brexit.
Mr Jenrick, the housing secretary, took to the airwaves to deny the claims, saying: “We think that the new deal the prime minister has negotiated, which is a good deal, enables the whole of the UK to leave the EU customs union and that means that we can now strike our own free trade deals around the world.”
Asked if the president was wrong, he said: “We know that this is a deal which enables us to secure good deals with a range of growing economies around the world including the US and we will be setting out to do that.”
Former international trade secretary Liam Fox also questioned the president’s remarks.
He said: “Well I don’t know what they are, because we’re leaving the European Union customs union as a single country and that will enable us – under WTO rules – to establish an independent trade policy, and be able to move forward.
“Perhaps it’s the fact that when we have done trade agreements elsewhere, for example with Canada in the EU, we made very clear that we are going to protect things like food standards and our rights to regulate the health service now. We are not going to give those up.”
Mr Trump also criticised Jeremy Corbyn during the interview, saying he was “so bad for your country”.
Labour’s shadow international trade secretary Barry Gardiner hit back, saying: “Of course he sides with the super-rich, Labour doesn’t.
“So, it’s no surprise to me that he thinks it would be bad news for people like him.”
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