ReutersPresident Trump has spoken of his warm relationship with King CharlesKing Charles and Queen Camilla will meet US President Donald Trump in late April, as a state visit to the United States has been confirmed by Buckingham Palace.
On the way back, the King will pay a visit to Bermuda, a British Overseas Territory in the North Atlantic.
The US trip has been expected for some time, but such visits are carried out on behalf of the UK government - and an official announcement appeared to have been waiting for a gap in the political tensions over the Iran war.
Details of the itinerary in the US have still to be released, but it will include Washington DC, in what will be the first UK state visit to the US since Queen Elizabeth II's visit in 2007.
The visit will include a state dinner at the White House and the King will deliver an address to Congress.
The US marks its 250th anniversary of independence this year - and that will be a significant focus of the trip, with Buckingham Palace saying the trip will "celebrate the historic connections and the modern bilateral relationship" between the countries.
Shortly before the trip was announced on Tuesday, President Trump lashed out at the UK and other countries over the Iran war, telling them to "go get your own oil" from the Strait of Hormuz and "the USA won't be there to help you anymore, just like you weren't there for us".
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Ever since President Trump's visit to the UK last September, there has been speculation about the King carrying out a return visit.
The US president's visit to Windsor Castle seemed to have smoothed UK-US relations, with Trump last week saying of his time with the King: "He honoured me and our country... we had an amazing time."
Trump also spoke of the warmth of his personal relationship with the King - "I think he's fantastic" - and the president said he was looking forward to hosting the King at a state banquet.
There is also likely to be interest in whether the King will meet his son Prince Harry, who lives in the US, during the visit.
ReutersPresident Trump said he felt "honoured" by his reception in Windsor last yearBut there have been political differences, including over the war in Iran, in which Trump publicly criticised UK Prime Minister Sir Keir Starmer as "no Winston Churchill".
That followed a previous dispute when UK veterans were angered by an apparent downplaying by Trump of the UK's military involvement in Afghanistan.
Both rows had raised questions about whether a state visit to the US in April should go ahead - with Lib Dem leader Sir Ed Davey saying it should be cancelled.
A YouGov survey last week suggested that 49% of the British public were against the state visit to the US while 33% wanted it to go ahead.
The visit also comes in the wake of Andrew Mountbatten-Windsor's arrest - and US Congressman Ro Khanna has called for King Charles to meet survivors of the sex offender Jeffrey Epstein.
"As you are aware, this is not solely an American matter," Khanna wrote in a letter to the King on Monday.
Mountbatten-Windsor has always denied any wrongdoing from his links to Epstein.
But while the formal announcement of the state visit might have been delayed, planning seems to have quietly continued in the background, with no signs of the visit being stopped.
The decision to hold a state visit is made by the government, with the King travelling on behalf of the Foreign Office.
Trump appears to be fascinated with the monarchy and to greatly value his relationship with King Charles - and the UK government seems ready to leverage this to improve links with the US and to reduce diplomatic tensions.
UK Royal FamilyDonald TrumpKing Charles III
