U.S. President Donald Trump kicked off his historic second state visit to Britain on Wednesday amid unprecedented pomp, intense security, technology investments and protests as King Charles and other royals welcomed their nation's closest ally.
Trump and his wife Melania are being hosted by the king at Windsor Castle, the oldest and largest inhabited castle in the world and family home to British monarchs for almost 1,000 years, where he is being treated to the full array of British pageantry from a carriage procession to a lavish banquet.
Britain laid on what it said was the largest military ceremonial welcome for a state visit in living memory, and Trump, an overt royal fan, has made little secret of his delight at being not just the first U.S. leader, but the first elected politician to be invited for two state visits.
"It's a very special place," Trump said, adding that he loved Britain.
UK HOPES VISIT WILL CEMENT 'SPECIAL RELATIONSHIP'
Prime Minister Keir Starmer is hoping to use that sentiment to Britain's advantage as his government seeks to use the trip to cement the two nations' "special relationship", deepen economic ties, secure billions of dollars of investment, discuss tariffs and press Trump on Ukraine and Israel.
Companies including Microsoft, Nvidia, Google and OpenAI have already pledged 31 billion pounds ($42 billion) in British investments over the next few years, in AI, quantum computing and civil nuclear energy.
Starmer also wants further progress on trade, after Britain secured the first deal with Trump to lower some tariffs. Talks may touch on remaining levies on steel, whisky and salmon.
"They want to see if they can refine the trade deal a little bit," Trump said on Tuesday.
But while Starmer is banking on the royals to help cajole the anglophile president, whose mother came from Scotland, many pitfalls for Britain's prime minister remain.
Polls show Trump is widely unpopular in Britain and Starmer, faced with plummeting poll ratings of his own and economic woes, will need to show that his royal trump card can reap benefits.
PROTESTERS PULL OFF EPSTEIN STUNT DESPITE HIGH SECURITY
Awkward questions about late sex offender Jeffrey Epstein could also come to the fore.
Last week, Starmer sacked Peter Mandelson as Britain's ambassador to Washington over his ties to Epstein, which could lead to questions for both the premier and Trump, whose own relationship with the financier has also come under scrutiny.
While there was a massive security operation in place in Windsor, police said four people had been arrested on Tuesday after images of Trump alongside Epstein were projected onto one of the castle's towers. Trump was not there at the time.
Crowds of Trump supporters gathered in Windsor but in London thousands marched to protest against the state visit.
"I quite simply dislike everything that Trump and his administration represent around the globe," retiree Bryan Murray said.
TRUMP DAZZLED BY PAGEANTRY
While the focus on Thursday will be on geopolitics and trade when Starmer hosts Trump at his Chequers country residence, Wednesday was all about ceremony.
Trump and Melania joined Charles, his wife Queen Camilla and other royals and dignitaries for a carriage procession, with the route lined by 1,300 British service personnel. The president, occasionally chatting and smiling with the king, then inspected a guard of soldiers who wore scarlet uniforms and bearskin hats.
Later, the Trumps viewed historical items from the Royal Collection relating to the U.S., and then visited St George's Chapel, the final resting place of Queen Elizabeth, who hosted Trump for his first state visit in 2019, to lay a wreath on her tomb. She died in September 2022.
There was a further military parade and a flypast by Britain's Red Arrows aerobatics team, but poor weather meant British and U.S. F-35 military jets - a symbol of bilateral defence collaboration - could not join.
The Trumps also found time for a private meeting with the king's "very handsome" elder son Prince William - as the president has called him - and the heir's wife Kate, which was described by the prince's spokesperson as "warm and friendly".
Events on Wednesday will conclude with an opulent state banquet where the king and president will make speeches.
For Charles, 76, the visit might provoke mixed emotions. He has little obviously in common with Trump, from his 50 years of championing environmental causes to his efforts to bring harmony between religions and his recent steadfast support for Canada, where he is head of state.
But the occasion will also afford him the greatest global attention since his coronation.
"If it goes well... I think this will go down as the most consequential event in his reign," said historian Anthony Seldon. ($1 = 0.7333 pounds)