Starmer has faced almost daily attacks from the President since he blocked the US from using Diego Garcia, the joint British-US base in the Indian Ocean, to carry out strikes on Iran and refused to send ships to reopen the Strait of Hormuz.
During the President’s Telegraph interview, the first part of which was published earlier on Wednesday, he revealed that he was considering withdrawing from Nato.
The state visit to Washington will be an opportunity to reset broader UK relations with the US, with the King taking on greater political relevance than when his mother was monarch.
Trump told the Telegraph that the King was “a friend of mine”, adding that he had “nothing to do with this”, in reference to the breakdown in US-UK relations over the Iran war. The King holds the legal power to declare war under the royal prerogative but, in practice, the monarch cannot become involved in politics.
“I have a great relationship with King Charles, I’ve known him a long time,” Trump said.
“He’s a wonderful and brave man, to be honest with you. He’s been through a lot, in many ways.”
Trump has long been an admirer of the royal family. His fascination is thought to be rooted in his respect for the late Queen Elizabeth, whom he met twice.
One diplomatic source told the Telegraph that Trump and Charles were in regular correspondence, often writing letters to each other.
Trump and Starmer are not thought to have spoken in the weeks before the President criticised the Prime Minister for failing to stand by the US in the war with Iran.
British diplomats in Washington hope the King can help repair the fractured special relationship during the visit.
A full itinerary of the trip is yet to be announced, but the programme will include a state dinner at the White House and an address to Congress.
It is widely expected that the King and Queen will also visit New York. The King will then make a solo visit to Bermuda, his first visit as King to a British Overseas Territory and the first visit to the island by a reigning king.
During Trump’s second state visit to the UK in September last year, he was driven around Windsor Castle’s estate in the Irish State Coach before inspecting an honour guard and watching a Red Arrows flypast.
Later the same evening, 160 guests, mostly drawn from the worlds of politics and business, assembled in St George’s Hall for a state banquet.
The visit will be the King’s 20th to the US, but his first as monarch. In 2005, the King and Queen went to the country for their first joint official tour after they married.
For the 200th anniversary of US independence, the late Queen and Prince Philip travelled to America in a show of friendship, with the Queen delivering a speech about George III, her ancestor, and his defeat at the hands of colonial rebels.
During the state visit last year, the King played a critical role in persuading Trump that Ukraine could win the war against Russia, which ultimately led to a change in the President’s position.
The King has been a staunch supporter of Ukraine’s resistance against the Russian invasion.
He hosted Volodymyr Zelenskyy, the Ukrainian President, at Sandringham for tea, days after the Ukrainian leader’s bruising encounter with Trump and Vice-President JD Vance in the White House. His position on the war in Iran is less clear.
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