The UK could have a trade deal with the US “overnight” if the UK agrees to a “free, open border” between the two countries, according to Donald Trump’s former chief economic adviser.

Gary Cohn, who was adviser to the US President from 2017 to 2018, also said a no-deal Brexit would be better than “the state we’re in right now”, and urged the UK to make progress in “solving” Brexit.

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Speaking on BBC Radio 4’s Today Programme, Mr Cohn said: “Any forward progress at this point is good.

“This is another one of those economic geopolitical situations that has to be solved. And if it’s hard, soft, it has to be solved.

“And countries are more resilient than people think and, if you end up at the hard Brexit and say ‘we’re out, no-deal, we’ll be out on this day’ things will tend to happen, things will fall into place.

“You’ll have to get certain things done to make sure it works and then it will evolve over time. But it’s better than the state we’re in right now where every month or every six weeks there’s a new drama and we just kick the can down the road.”

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Mr Cohn said the UK could have a trade deal with the US “overnight” if it is willing to agree to an open border.

Mr Cohn said: “The President has always said free, fair, open, reciprocal. You’re calling him in on what he’s always said.

“So, he’ll go tariff for tariff, if you tariff something, he’ll tariff something, if you don’t tariff anything, that would be an interesting discussion to say ‘hey, look, we’ll do a free, open border with you, you do a free open border with us, no tariff for no tariff. That should get you a deal overnight.”

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Mr Cohn said: “You talk about the United States being stymied in capital investment.

“The only place that makes the United States look like we’ve got a lot of capital investment is the UK because literally you have no capital investment going on right now.”