Liz Truss ripped up the royal rulebook when she met King Charles for the first time after he returned from Balmoral. On Friday, in her first audience with the King, the new Prime Minister was spotted to grip the Monarch's left arm tightly as they spoke.

In their meeting, she expressed her 'very, very sincere condolences' and the King confided that his mother's death had been 'the moment I've been dreading'. Now Royal biographer and historian Hugo Vickers has said that while the PM did break protocol by touching his arm, he expected that the King 'wouldn't have minded in the least'.

Liz Truss could be seen touching the new King's arm - an apparent breach of protocol, technically (
Image:
ALPR/AdMedia / SplashNews.com)
The monarch told the new PM he had been 'dreading' this day (
Image:
ALPR/AdMedia / SplashNews.com)

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He told the Mail on Sunday: "On a very strict interpretation of Royal protocol rules, the PM should not have held the King's arm in this way.

"The rules are that you leave it to the King to do the arm touching. The Royal Family is supposed to initiate the contact. You don't do anything - you keep yourself to yourself."

But he thought Ms Truss's kind gesture wouldn't have bothered the King, adding: "On this occasion, I would give her [Ms Truss] the benefit of the doubt and being sympathetic to the King at this very emotional moment.

William was seen hugging an emotional resident, during a visit to the Wheatley Group in Glasgow (
Image:
PA)

"It was probably the point where King Charles said that he had been dreading this moment. He certainly wouldn't have minded in the least and that's what it comes down to."

As she met King Charles at Buckingham Palace, the PM curtsied after being announced, before the pair shared a handshake.

As she offered her condolences, Charles thanked her, saying: “You are very kind for coming – I know how busy you are.”

Michelle Obama reportedly broke royal protocol - but it's clear the Queen was, sort of, hugging her back

He added: "But it’s been so touching this afternoon when we arrived here, all those people come to give their condolences.”

Ms Truss again repeated: "Your Majesty, my very greatest sympathies.”

He replied: "You are very kind. It was the moment I have been dreading, as I know a lot of people have. We’ll try keep everything going. Come, come have a seat.”

Previously Michelle Obama - wife of then US President Barack Obama reached in for a hug with Her Majesty while at Buckingham Palace - and added she had no regrets.

In her 2018 memoirs the First Lady wrote: "If I hadn't done the proper thing at Buckingham Palace, I had at least done the human thing.'

She also said the Queen dubbed the protocol rules 'rubbish' after asking the First Lady to ignore the royal protocol and sit next to her in the car.

Last night, a Number 10 source defended the PM's gesture, saying:"'It was a very human moment - Liz wanted to express her deepest condolences to a son who had lost his mother."

* This weekend, the Daily Mirror and Sunday Mirror celebrate the life of Her Majesty the Queen with a commemorative special filled with all the key moments from Britain’s longest reigning monarch. Be sure to pick up your copy of the Daily Mirror and Sunday Mirror to get poth pullouts.