Theresa May and Donald Trump will this week hold talks over a US-UK trade deal that slashes tariffs and makes it easier for hundreds of thousands of workers to move between the two countries.

The Prime Minister will on Friday become the first foreign leader to hold talks with the new President in the White House following assurances by Mr Trump’s team that he wants to do a major free trade deal with Britain that can be announced in the weeks after Brexit.

One option understood to be being discussed in Whitehall is to agree to cut – or even drop – tariffs on items Britain and America already export to one another.