US President Donald Trump welcomed King Charles III to the White House for a visit fraught with doubt about the future of Britain’s so-called special relationship with America and fresh security concerns in the wake of the shooting at the White House correspondents’ dinner.

The British monarch and his wife, Queen Camilla, were greeted by the president and First Lady Melania Trump on Monday at the start of a four-day trip, his first state visit to the US since becoming king in 2022. The couples exchanged handshakes and posed for a photo at the South Portico of the White House before walking inside.

The long-planned event is intended to mark the 250th anniversary of the US’s independence from Britain, though its diplomatic mission has taken on new urgency amid Trump’s recent feud with Prime Minister Keir Starmer over the UK’s limited support for US military action against Iran.

The UK has decided to go ahead with the visit despite Saturday’s shooting at the hotel that hosted the annual press gala. Trump said on Sunday that the king would be “very safe” during a program that includes a military review at the White House and a speech to a joint session of Congress.

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“The King and Queen are most grateful to all those who have worked at pace to ensure this remains the case and are looking forward to the visit getting underway,” Buckingham Palace said on Sunday.

It’s the first state visit by a British monarch since Charles’ mother, Queen Elizabeth II, made the trip in 2007. The late queen similarly addressed Congress in 1991. The four are sharing afternoon tea and touring an expanded beehive at the presidential mansion, before the king and queen depart for a garden party at the British ambassador’s residence.

“Every aspect of the White House program has been thoughtfully designed by President Trump and First Lady Melania Trump to celebrate our rich shared history — and to look forward to the next 250 years of the special relationship,” said Ambassador Monica Crowley, Chief of Protocol of the United States.

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The visit comes at a fraught time for UK-US relations, which are perhaps at their lowest point since the Suez Crisis in the 1950s. While Trump has only heaped praise on Charles, he’s repeatedly criticized Starmer, dismissing the UK’s elected prime minister as weak and unreliable.

US House Minority Leader Hakeem Jeffries said Monday that while the relationship remains special, “toxic Republican policies for the last 15 months or so are eroding” it. “Hopefully the King’s visit is going to go a long way toward repairing the damage that this administration has done to one of our most important allies,” he said.

Trump and Charles will meet again on Tuesday, with the king expected to stress the importance of the deep and enduring relationship between the two allies. After two days in Washington, the king and queen will travel to New York to commemorate the Sept. 11 attacks, visit a community organization mentoring children affected by food insecurity and attend an event with senior business leaders.

The pair will then travel to Virginia for a block party and visit a national park before departing to Bermuda, a British overseas territory.