Crowds cheered for King Charles III in Wales on Friday though some voiced protest against his ascent to the throne, as footballing royalty David Beckham joined a miles-long queue to mourn the late queen in London.

In Cardiff, Charles met in private with Welsh First Minister Mark Drakeford, an avowed republican, and there was isolated booing on the streets after the new monarch was quick to declare his son William the new Prince of Wales.

But Drakeford said questions over the future of the monarchy would "be a footnote to the dominant feelings of the day", following the death on September 8 of Queen Elizabeth II at the age of 96.

Large crowds chanted "God save the king" as Charles shook hands with well-wishers following a multi-faith service in Llandaff Cathedral, and at Cardiff Castle, on the last of his visits to the UK's four nations.

In a speech at the parliament of Wales, which alternated between English and Welsh, he vowed to follow the "selfless example" of Britain's longest-serving monarch.

Charles added that William's "love for this corner of the Earth is made all the greater by the years he himself has spent here" -- after his heir trained as a Royal Air Force helicopter pilot in Anglesey.

Outside Cardiff Castle, a few protesters held up banners declaring "Abolish the Monarchy", "Citizen not subject" and "Democracy now".

On his return to London, Charles was due to join his siblings -- Princess Anne, Prince Andrew and Prince Edward -- for a family vigil in front of the flag-shrouded casket as it lies in state in London.

- Playing for the queen -

The "Vigil of the Princes", with all four royals in ceremonial military uniform, will last for 15 minutes from 1830 GMT.

Eight of the queen's grandchildren, including William and his brother Harry, are expected to hold a similar vigil on Saturday evening.

Elizabeth's death has triggered an outpouring of emotion, with tens of thousands from all backgrounds and many nations queueing for hours, often through the night, to pay their respects in Westminster Hall.

The queue was paused on Friday after a park at the end of the line along the River Thames reached capacity, the government said, warning that those at the end faced a wait of 14 hours.

It resumed nearly an hour later. Beckham, the footballer turned fashion icon, was near the front in the afternoon after joining it in the early hours of Friday.

"I thought by coming at 2:00 am it was going to be a little bit quieter -- I was wrong," Beckham told ITV News, as selfie-seeking fans briefly held the queue up.

The ex-Manchester United and Real Madrid star said every time the national anthem -- then entitled "God Save the Queen" -- had been played at England matches "meant so much to us".

Another queueing was Peter Stratford, 70, a former firefighter who was one of the first on the scene of a huge fire in 1992 at Windsor Castle, where the queen will be buried on Monday.

"My ankles are killing me, but it's a small sacrifice to make," he told AFP after waiting in line for eight hours.

"I've been tearful, emotional... I wouldn't have missed it."

At Westminster Abbey on Monday morning, the queen will be honoured with Britain's first state funeral in nearly six decades, with more than 2,000 guests expected.

- Row with China -

After the televised service, the coffin will be transferred by royal hearse to Windsor Castle, west of London, for a family-only burial in which the queen will be laid to rest alongside her late husband Philip, parents and sister.

US President Joe Biden, Australian leader Anthony Albanese, Canadian Prime Minister Justin Trudeau and French President Emmanuel Macron have all confirmed their attendance at the funeral, as have Japan's Emperor Naruhito and numerous other royals.

Police are mounting Britain's biggest-ever security operation for the funeral, as the global dignitaries jet in and crowds file past the queen's casket round the clock all weekend.

Early Friday, two police officers were stabbed in central London, one suffering "life-changing" injuries, the Metropolitan force said, but it ruled out any link to terrorism.

An official delegation from China has been banned from attending the lying-in-state following an intervention by House of Commons Speaker Lindsay Hoyle, parliamentary sources said.

It comes after China sanctioned several British lawmakers over their criticism of the country's human rights record.

"As the hosts, the British side should uphold both diplomatic courtesy and gracious hospitality," foreign ministry spokeswoman Mao Ning told reporters in Beijing.

Downing Street refused to comment.

- 'Waste of money' -

In Westminster Hall, the sombre atmosphere is completed with members of the king's guard in ceremonial uniform posted around the podium in a constant vigil.

Mourners marked their moment in front of the coffin in various ways, from bows or curtsies to the sign of the cross or by simply removing their hats, an AFP reporter observed Friday.

Some wiped away tears. Others brought infants in pushchairs. Old soldiers stopped and gave one last salute to their former commander-in-chief.

Meanwhile, in Cardiff, many had waited for hours ahead of Charles's visit.

"Something like this won't happen again," said barman Jack Grimshaw, 27, who turned out with his young son.

"The royal family has been around for so many years (but) we didn't have a new king for so long."

Not everyone was happy to see the new monarch in Wales. Zahra Ameri, 22, said the funeral was a "waste of money".

"I'm hoping that Wales becomes independent. Of course, it would be a disturbance in our economy because we do rely on the UK, but I strongly believe in independence," she said.