Trump tells BBC that King's visit could 'absolutely' help repair relations with UK

"I know him well, I've known him for years," he said. "He's a brave man, and he's a great man. They would absolutely be a positive."

The president also spoke about his relationship with UK Prime Minister Keir Starmer, who he said could only "recover" if he changed course on immigration.

The King and Queen will travel to the US for a four-day visit beginning on Monday, and will meet with Trump at the White House.

The King will have a private meeting with the president and also deliver an address to Congress.

After two days in Washington DC, they will travel to New York, Virginia and Bermuda before returning to the UK.

The Foreign Office said the trip will mark the 250th anniversary of US independence, and will celebrate a partnership of "shared prosperity, security and history".

In the five-minute interview on Thursday, Trump was also asked about his relationship with UK Prime Minister Keir Starmer.

The two leaders have appeared at odds over the war in Iran, and Sir Keir has faced mounting pressure over his decision to appoint Lord Mandelson as UK ambassador to the US.

In a post on Truth Social on Monday, Trump said Lord Mandelson was "a really bad pick" but the prime minister had "plenty of time to recover".

When asked what he meant by that post, Trump said: "If he opened the North Sea and if his immigration policies became strong, which right now they're not, he can recover, but if he doesn't, I don't think he has a chance."

Trump has repeatedly called on the UK to increase oil and gas extraction in the North Sea.

"I make my decisions based on what's in the British national interest and not what other people say or do," Sir Keir said while talking to broadcasters about the president's comments on Thursday.

"That is why I took the decision that we would not be dragged into the war in Iran," he said. "I'm not going to be diverted or deflected from that by what anybody else says."

Trump has also criticised the UK government and other allies over their response to the Iran war. He has said he is "not happy" with the level of support offered by the UK, while Sir Keir has repeatedly said the country will not be drawn into a wider conflict.

"We've wiped Iran's military out, he added. "I didn't need anybody."

"I wanted to see whether or not they would be involved," Trump said, describing his calls for support from allies as "more of a test".

Trump was also asked whether his threat, made earlier this month, that "a whole civilisation will die tonight" unless Iran agreed to a deal was about nuclear weapons. The comment was widely condemned, including by the Pope, the head of the UN and Sir Keir.

"The other side is dying to make a deal," Trump said. "So whatever I'm saying or whatever I'm doing, it seems to be working very well."

He is suing over the way a Panorama documentary edited together different sections of a speech he gave before the Capitol riot on 6 January 2021.

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The justice department's inspector general will review the withholding and overdue release of secret files.

The prime minister's comments come after a US trade official said the US might have to take action over a provincial boycott of American wine and spirits.

My five-minute phone call with President TrumpSarah Smith asked the president about King Charles's upcoming visit, the state of the so-called special relationship and the war with Iran.

Conflict spread across the Middle East after the US and Israel launched strikes on Iran on 28 February.