Trump to make unprecedented second state visit to the U.K. in September

President Donald Trump will make an unprecedented second state visit to the United Kingdom in September along with first lady Melania Trump, where he will be hosted by King Charles III and Queen Camilla, Buckingham Palace said in a statement Sunday.

No American president has ever been invited for a second state visit. But Trump, a big supporter of the royal family, was hosted by Charles' late mother, Queen Elizabeth II, in 2019.

On this occasion, however, he will not stay at Buckingham Palace, which is currently undergoing renovations. Instead, he will travel to Windsor Castle, which sits around 30 miles to the west of London.

Trump who shocked reporters and palace pundits in 2018 when he breached royal protocol by walking ahead of the queen, at times blocking her view and giving her his back, said it was a “great, great honor” when British Prime Minister Keir Starmer hand-delivered the invitation during a visit to the White House in February.

“That’s really something,” he added.

Second-term U.S. presidents who have already made a state visit to the U.K. normally take lunch or tea with the monarch, as was the case with Presidents George W. Bush and Barack Obama. Meanwhile, state visits are ceremonial meetings between heads of state that are used to honor friendly nations and sometimes smooth relations between rivals.

Although the king formally issues the invitation for a state visit, which comes with a full display of pageantry and royal pomp, he does so on the advice of the government.

The announcement comes as Starmer courts Trump's favor on tariff negotiations, which have thrown a wrench in the Labour government's efforts to grow the British economy after it contracted in April amid a record fall in exports to the United States.

Trump last month lowered tariffs on the British aerospace sector to zero, but imports of British steel products continue to face a 25% duty.

On his last visit to the U.K., Trump injected himself into British politics by endorsing Boris Johnson to be the next prime minister and weighing in on negotiations over Brexit. He also continued his public feud with London Mayor Sadiq Khan, branding him a loser.

Charles could also face challenges with Trump on Canada, since he's also the head of state for the former British colony. Trump has on several occasions threatened to annex Canada and suggested it should become the 51st U.S. state.

Canadian Prime Minister Mark Carney criticized the state visit invite in May.

In a speech to the Canadian Parliament in May, Charles highlighted the country's "sovereignty" and said it was facing a "critical moment."

“The true north is indeed strong and free,” he said, referring to Canada's national anthem.

This article was originally published on NBCNews.com