LONDON — Arriving to a royal welcome from the British monarch and government and a collective raspberry from much of the public, President Donald Trump landed in England on Monday morning for his first official state visit to the U.K. — one that comes directly on the heels of the American president injecting himself into British domestic politics.

In addition to weighing in on a race for the prime minister's job and negotiations over Brexit this weekend, Trump managed to ruffle British feathers while he was still on Air Force One. In a pair of tweets sent Monday just before he stepped off the plane, Trump continued his public feud with London Mayor Sadiq Khan, who wrote a scathing opinion piece about Trump in a weekend newspaper.

....Kahn reminds me very much of our very dumb and incompetent Mayor of NYC, de Blasio, who has also done a terrible job - only half his height. In any event, I look forward to being a great friend to the United Kingdom, and am looking very much forward to my visit. Landing now! — Donald J. Trump (@realDonaldTrump) June 3, 2019

A mostly ceremonial trip that will wrap up in France with commemorations of the 75th anniversary of the Allies storming the beach at Normandy, Trump's visit promises to mix in statecraft at the margins of an official schedule full of pomp.

It was the latter on the menu at Buckingham Palace, where the president and first lady Melania Trump made their first official stop shortly after noon local time. Touching down in Marine One on the sweeping garden beneath the West Terrace of Queen Elizabeth II's residence and administrative headquarters, the Trumps were greeted by Charles, Prince of Wales, and Camilla Parker Bowles, the Duchess of Cornwall.

They took a short walk to a covered entryway, where the queen, wearing a chartreuse dress and matching hat, shook their hands and smiled before leading the first couple inside. The five-person party re-emerged a few minutes later for a welcoming ceremony led by the Guard of Honour, which played American standards such as the national anthem,"The U.S. Air Force," "The U.S. Army Goes Rolling Along" and "The Marines' Hymn."

The Trumps were invited to stay for a luncheon and a review of royal gifts.

Later, they visited Westminster Abbey, the site of coronations and royal weddings, as well as the final resting spot of 17 monarchs, Isaac Newton, Stephen Hawking and Charles Darwin. After tea with the prince and duchess, they returned to Buckingham Palace for a state banquet in the evening, where Trump and the queen toasted their countries' historic bonds in wartime and in peace.

"On behalf of all Americans, I offer a toast to the eternal friendship of our people, the vitality of our nations, and to the long, cherished, and truly remarkable reign of her majesty the queen," Trump said.

The main events are intended to demonstrate the closeness of the "special relationship" between the two countries.

"Our relationship has underpinned our countries’ security and prosperity for many years — and will continue to do so for generations to come," Prime Minister Theresa May said in a statement.

But Trump's decision to insert himself into British politics — and his use of the word "nasty" in conjunction with the Duchess of Sussex, the former Meghan Markle — created new tension just before his departure. Trump endorsed nationalist-leaning former London Mayor Boris Johnson in the Conservative Party race to succeed May, who is stepping down Friday.

Though not out of character for Trump, the decision to intervene in a factional contest in a foreign country was a rare move for an American president. He has also urged Britain to walk away from talks to smooth its exit from the European Union if it doesn't like the deal on the table.

Trump plans to meet Tuesday with May in the main policy-focused event of his trip. British and American experts say they expect trade and security issues to be at the forefront of their discussion.

At the end of the day, Trump tweeted about the trade talks, saying the London leg of the trip was "going really well."

London part of trip is going really well. The Queen and the entire Royal family have been fantastic. The relationship with the United Kingdom is very strong. Tremendous crowds of well wishers and people that love our Country. Haven’t seen any protests yet, but I’m sure the.... — Donald J. Trump (@realDonaldTrump) June 3, 2019