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Trump makes unprecedented second state visit

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Royals to host lavish banquet for Trump

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Four arrested after image projected on to Windsor Castle

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Under-fire Starmer hails technology investment

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Questions over Epstein among potential pitfalls

(Recasts after start of visit, with new details throughout)

By Sam Tabahriti and Michael Holden

WINDSOR, England, Sept 17 (Reuters) -

King Charles greeted Donald Trump on Wednesday as the U.S.

president's historic second state visit to Britain began with

unprecedented pomp, intense security, technology investments and

planned protests.

Trump and his wife Melania arrived at Windsor Castle,

the oldest and largest inhabited castle in the world and family

home to British monarchs for almost 1,000 years, where the royal

red carpet treatment includes a carriage procession, gun

salutes, a military flypast and lavish banquet.

Britain says it will be the largest military ceremonial

welcome for a state visit in living memory.

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 by a British monarch for two

visits.

On his arrival, he told reporters he loved Britain. "It's a

very special place," he said.

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 cement the two

nations' "special relationship", deepen economic ties, secure

billions of dollars of investment, discuss tariffs and press the

U.S. president on Ukraine and Israel.

The visit has already delivered a new technology pact

between the two countries with companies from Microsoft ( MSFT ) to

Nvidia ( NVDA ), Google and OpenAI pledging 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 tariffs.

"Basically, I'm there also on trade. They want to see if

they can refine the trade deal a little bit," Trump said when he

left the White House for Britain on Tuesday.

"They'd like to see if they could get a little bit better

deal, so we'll talk to them."

But while Starmer is banking on the unrivalled royal allure

helping cajole the anglophile president, many pitfalls for

British 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 playing his royal trump

card will reap benefits.

Awkward questions about late sex offender Jeffrey

Epstein could also come to the fore.

Starmer, last week, sacked Peter Mandelson as Britain's

ambassador in Washington over his ties to Epstein, which could

lead to questions for both Starmer and Trump, whose own

relationship with the financier has also come under scrutiny.

PROTESTERS PULL OFF EPSTEIN STUNT DESPITE HIGH SECURITY

While security for the visit was tight, with a massive

police operation in place in Windsor, protesters pulled off a

stunt in Windsor on Tuesday.

Police said four people were arrested for malicious

communications after images of Trump alongside Epstein were

projected on to one of Windsor Castle's towers. Trump was not in

Windsor at the time.

Large protests are also expected in London on Wednesday with

1,600 officers deployed to deal with a demonstration by the

"Stop the Trump Coalition".

Commuters in the capital had mixed views about the visit,

with some angry about the invitation and others saying it was

smart politics and a good use of Britain's soft power.

"We're looking to sort of make the best of a bad situation,"

said lawyer Kirstie Robertshaw, 54.

TRUMP TO BE DAZZLED BY PAGEANTRY

Wednesday will be dominated by ceremony. Trump and his wife

Melania were greeted by the king's "very handsome" son Prince

William - as the president has called him - and the heir's wife

Kate.

Charles and his wife Queen Camilla, who was able to attend

after recovering from sinusitis, will then join the Trumps on a

carriage procession through the grounds of the castle, with the

route lined by 1,300 British service personnel.

The royals will show the president and first lady historical

items from the Royal Collection relating to the U.S., before the

Trumps visit St George's Chapel, the final resting place of

Queen Elizabeth, who hosted Trump for his first state visit in

2019, where he will lay a wreath on her tomb.

Later there will be a flypast by military aircraft before

the state banquet.

For Charles himself, the visit might provoke mixed emotions.

He has little obviously in common with Trump, from his 50

years 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.

On Thursday, the action will move to Starmer's Chequers

country residence, where the focus will be on geopolitics.

($1 = 0.7333 pounds)

(Additional reporting by Elizabeth Piper, Paul Sandle and

Alistair Smout; writing by Michael Holden; editing by Kate

Holton, Alexandra Hudson, Ros Russell, Alex Richardson, Philippa

Fletcher)