WASHINGTON (AP) — Two and a half centuries after the American colonies declared independence from Britain under King George III, his descendant King Charles III lands in Washington on Monday with trans-Atlantic ties under strain and security in the spotlight.

President Donald Trump and first lady Melania Trump are expected to greet King Charles III and Queen Camilla at 4:15 p.m. EDT. Watch live in our video player above.

A shooting at a Washington dinner attended by President Donald Trump on Saturday sparked a last-minute security review of the four-day state visit, intended to celebrate the United States' 250th anniversary, and the U.S.-U.K. "special relationship."

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Buckingham Palace said the king "is greatly relieved to hear that the president, first lady and all guests have been unharmed." After a security review, the palace said the trip "will proceed as planned."

Trump praises the king but derides Starmer

A rift between the U.K. government and Trump over issues including the Iran war had already raised the political stakes for the British monarch's visit.

In recent weeks, Trump has lambasted Prime Minister Keir Starmer over his unwillingness to join U.S. military attacks on Iran, dismissing Britain's leader as "not Winston Churchill," the World War II prime minister who coined the phrase "special relationship" for the U.K.-U.S. bond.

It's part of a wider rift between Trump and the United States' NATO allies, whom he has called "cowards" and "useless" for not joining action against Iran. A leaked Pentagon email suggested the U.S. could reassess support for the U.K.'s sovereignty over the Falkland Islands in the south Atlantic. Britain and Argentina fought a 1982 war over the islands, also known as the Islas Malvinas.

The president insists the political chill won't affect the royal visit. Charles "has nothing to do with that," Trump said in March, meaning NATO.

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The president has spoken in glowing terms about Charles, repeatedly referring to the monarch as his "friend" and a "great guy."

He also continues to mention his "amazing" trip to the U.K. in September with first lady Melania Trump for an unprecedented second state visit. Starmer hand-delivered the invitation from the king in the Oval Office five weeks after Trump returned to office, in a very public attempt to woo the Republican president.

The U.K. royal family laid on pomp and pageantry for the Trumps, with scarlet-clad guardsmen, brass bands and a sumptuous banquet at Windsor Castle.

"President Trump has always had great respect for King Charles, and their relationship was further strengthened by the president's historic visit to the United Kingdom last year," White House spokesperson Anna Kelly told The Associated Press. "The president looks forward to a special visit by Their Majesties, which will include a beautiful state dinner and multiple events throughout the week."

Trump, meanwhile, told the BBC that the king's visit could "absolutely" help repair the trans-Atlantic relationship.

"He's fantastic. He's a fantastic man. Absolutely the answer is yes," the president said.

Some have called for the trip to be canceled

Kristofer Allerfeldt, a University of Exeter professor specializing in American history, said the two governments have very different objectives for the trip.

He said that for Charles, the trip is about "reinforcing long-term ties, showcasing the monarchy's soft power and reminding the world that Britain still carries diplomatic weight."

For Trump, it's more about "a media event," with emphasis on the optics of a visit that resembles a meeting of "two gilded monarchs."

Some U.K. politicians worry that the trip is fraught with opportunities for embarrassment. Trump's recent broadsides at Pope Leo XIV have heightened those concerns.

Ed Davey, leader of the U.K. centrist opposition Liberal Democrats party, earlier this month called Trump "a dangerous and corrupt gangster" and implored the government to cancel the trip.

"I really fear for what Trump might say or do while our king is forced to stand by his side," Davey said in the House of Commons. "We cannot put His Majesty in that position."

Starmer defended the visit, saying "the monarchy, through the bonds that it builds, is often able to reach through the decades" and bolster important relationships.

Andrew and Epstein cast a shadow

Raising the stakes is the shadow of the king's younger brother Andrew Mountbatten-Windsor, who has been stripped of his royal title of Prince Andrew, exiled from public life and put under police investigation over his friendship with Jeffrey Epstein. He has denied committing any crimes.

Epstein victims have urged the king to meet with them and other sexual abuse survivors. It's unlikely he will do so.

Charles has visited the U.S. 19 times, but this is his first state visit to the country since becoming king in 2022. His mother, Queen Elizabeth II, made four state visits to the U.S.

The king, who is 77 and was diagnosed in early 2024 with an undisclosed form of cancer, will spend four days in the U.S. accompanied by Queen Camilla.

In Washington, the king and queen will have a private tea with the Trumps and attend a garden party and a formal White House state dinner. The president and the king will also have a one-on-one meeting.

The royal couple will also visit the Sept. 11 memorial in New York and attend a 250th birthday block party in Virginia, where Charles will also meet Indigenous leaders involved in nature conservation — a favorite cause of the environmentalist king.

Three centuries after Britain's kings and queens gave up any real political power, the royals remain symbols of soft power, deployed by elected governments to smooth international relationships and send messages about what the U.K. considers important.

A key moment will be the king's speech to the U.S. Congress on Tuesday. It's only the second time, after Queen Elizabeth II in 1991, that a U.K. monarch has addressed a joint meeting of both houses.

Elizabeth praised liberalism on that trip, spoke against the idea that "power grows from the barrel of a gun" and praised the "rich ethnic and cultural diversity of both our societies."

The king's treasured causes, including the environment and harmony among religious faiths, are in contrast to Trump's. He's unlikely to accentuate differences, but Allerfeldt said that, in the monarch's subtle way, the king could use his speech to send a message.

"He does have an unorthodox way of looking at the world, and I think maybe he can actually have something valid to say when he addresses Congress," Allerfeldt said.

Jill Lawless reported from London.