Donald Trump will be an "honoured guest" when he visits Britain this week, the British ambassador to the United States has said.

Mr Trump will make his first visit to the UK as president where he will meet Prime Minister Theresa May at Chequers and the Queen at Windsor Castle on Thursday before travelling to Scotland.

A number of anti-Trump protests are planned to coincide with the visit, including a large balloon of the president in a nappy, which London Mayor Sadiq Khan has given permission for protesters to fly, but Sir Kim Darroch has said the Anglo-American alliance plays a "leading role".

Writing in the Sunday Telegraph, Sir Kim said the relationship between the United States and United Kingdom was "interwoven at every level", adding he was grateful for American support on a free trade agreement post-Brexit.

He wrote: "President Trump will be an honoured guest, representing a partnership that is greater and deeper than any other in history.

"And in a world in which the challenges seem ever more daunting, I'm confident that the UK-US alliance will continue to play a leading role in advancing our shared values of democracy and freedom."

Meanwhile, Sir Kim's American counterpart, Ambassador Woody Johnson, said Mr Trump was trying to get as much impact as possible from his 24 hours in the UK on what he described as a "very important" visit.