The US president used a speech at the state dinner for the King and Queen to claim that Charles agreed Iran could not have a nuclear weapon.

After a private meeting with the King in the Oval Office on Tuesday, President Trump told 120 guests in the East Room at the White House: “We’re doing a little Middle East work right now … and we’re doing very well.

“We have militarily defeated that particular opponent, and we’re never going to let that opponent ever, Charles agrees with me even more than I do, we’re never going to let that opponent have a nuclear weapon. They know that, and they’ve known it right now, very powerfully.”

Watch: Trump delivers speech at state dinner

While Trump has publicly criticised Sir Keir Starmer for not supporting the US and Israel’s actions in Iran, he has previously said that he felt the monarch would take a “different stand”.

Charles is said to be above politics; however, Trump’s latest intervention threatens to drag the King into the conflict in the Middle East.

The comments from the US president hinted that he discussed the Tehran conflict during private meetings over the visit. However, British officials suggested the president’s comments were in line with government policy.

The comments came during a night of laughter as the King cracked several jokes before guests dined on herb ravioli, Dover sole and White House honey and a vanilla bean dessert.

For the white tie dress code with no tiaras, the Queen wore a deep pink Fiona Clare evening gown and Garter sash with an amethyst and diamond necklace gifted by a former Duchess of Kent to Queen Victoria and then passed to Queen Mary.

US-BRITAIN-ROYALS-POLITICS-DIPLOMACYHenry NICHOLLS/AFP/Getty

The guest list was filled with Trump family, cabinet members and business figures; including Jeff Bezos, Tim Cook and Rory McIlroy, the golfer and Masters winner.

The East Room only fits 120 people, which has been used as further justification for urgency on Trump’s ballroom project. Referencing the project in his speech tonight, the King noted: “We made our own small attempt at real estate redevelopment of the White House in 1814”. 

The King won laughs when he pulled up the president on his recent claim that if it were not for the United States, European countries would be speaking German: “Dare I say that, if it wasn’t for us, you’d be speaking French.”

Charles presents the president with the bell from HMS Trump

Charles also revealed that his gift to his guest was a bell recovered from the aptly named HMS Trump, a Royal Navy submarine that fought in the Battle of the Pacific in the Second World War.

Charles said: “May it stand as a testimony to our nations’ shared history and shining future. And should you ever need to get hold of us … well, just give us a ring!” 

In another aside, Charles drew parallels between the low point of today’s alliance with the US and another low ebb after the Suez crisis.

The King said: “We have had our moments of difficulty even in more recent history. When my mother visited in 1957, not the least of her tasks was to help put the “special” back into our relationship after a crisis in the Middle East.”

He added, tongue in cheek: “Nearly 70 years on, it is hard to imagine anything like that happening today. But it is not hard to see how important the relationship remains, in matters both seen and unseen.”

State visit to the US - Day TwoPA/Aaron Chown

The visual signs, however, of that relationship were apparent earlier in the day during a formal welcome which showcased the best pomp and pageantry of the US military.

At a scale never seen at the White House before, the president gave a full ceremonial welcome on the south lawn for his royal guests, including a 21-gun salute and a flypast of F-45 fighter jets.

Noting the rain, Trump joked: “What a beautiful British day this is.” 

In a wide-ranging speech, he said that his late mother had loved the royal family.

Trump said: “Any time the Queen was involved in a ceremony or anything, my mother would be glued to the television and she’d say, ‘Look, Donald, look how beautiful that is’. She really did love the family.

“But I also remember her saying very clearly, ‘Charles, look, young Charles, he’s so cute’. My mother had a crush on Charles. Can you believe it? Amazing, how I wonder what she’s thinking right now.”

Trump described the UK as “a small but mighty kingdom across the sea” that had “the most cherished of friendships” with the US.

US Britain Royal Visit TrumpAP/Alex Brandon

Earlier in the day, however, a leaked conversation emerged in which Sir Christian Turner, the new UK ambassador to the US, appeared to have said that Israel was more likely to have a “special relationship” with the US than the UK.

Trump, however, said that “understanding of our nation’s unique bond and role in history” was “the essence of our special relationship”. 

Later, the two men sat down in the Oval Office for a meeting behind closed doors after Trump had described Charles as “an elegant man”, adding: “It’s great to have a King in here, a man of class.”

After a private meeting, Charles left to make a historic address to a joint meeting of Congress, becoming only the second monarch to do so after his late mother in 1991. In a diplomatic masterclass designed to appease and warn in equal measure, the King had 12 standing ovations from across the political divide as he made a historic speech in Washington.

Addressing a joint meeting of Congress on the second day of his visit, Charles managed to strike a blow for UK interests while acknowledging that the country should pull its weight by increasing defence spending.

In a speech which took 30 minutes to deliver as he kept stopping to be heard above the applause, the King said that the “special ingredient in our relationship” would be finding ways to agree, as he struck a conciliatory tone to “renew” the UK’s relationship with the US.

King Charles III addresses the US House of Representatives and Senate at the United States Capitol.Chris Jackson/PA

He also made a reference to the survivors of Jeffrey Epstein, speaking of the need to “support victims of some of the ills that, so tragically, exist in both our societies today”.

This, however, was primarily a speech to steady the ship after constant bombardment from the US president over the UK’s lack of support over Iran.

It was also the closest Charles came to making a political statement, referring to “my prime minister” and “my own parliament”, a reminder to Trump that the monarch travels at the request of the UK government.

“America’s words carry weight and meaning, as they have since independence,” the King said. “The actions of this great nation matter even more.”

Marking the 250th anniversary of independence, Charles, 77, added: “Ours is a partnership born out of dispute, but no less strong for it.

“Drawing on these values and traditions, time and again, our two countries have always found ways to come together. And by jove, Mr Speaker, when we have found that way to agree, what great change is brought about — not just for the benefit of our peoples, but of all peoples. This, I believe, is the special ingredient in our relationship”.

When the King and the president were reunited before the state banquet, Trump told reporters: “He made a very good speech. I’m very jealous.”