King Charles “did not dismiss” former Prime Minister Liz Truss when he greeted her with his “oh dear” comment at one of their first weekly audiences, according to royal author Robert Hardman.

The clip went viral back in September 2022, just after the death of Queen Elizabeth II, when the King was overheard murmuring the words “back again…dear oh dear” to Ms Truss, who went on to hold the record for the shortest time in office of any British PM at 49 days.

However, Mr Hardman has claimed that in fact His Majesty was “sympathising” with Ms Truss, who had already travelled to Buckingham Palace earlier that day for a Privy Council meeting and was trying to put her “at ease”.

He told Times Radio: “It’s a very King Charles-ish way of saying, ‘Oh, you poor thing, you’ve had to come back again’. It’s a sort of putting someone at their ease kind of remark.

“So the true story was actually he was being nice to her; it wasn’t an unguarded barb, it was actually good manners.”

For his new book Charles III: New King. New Court. The Inside Story, Mr Hardman interviewed the former PM, who had nothing but praise for the King.

Ms Truss said he was “very considerate” and even asked her to meet her daughters when she came to the Palace to formally announce her resignation.

Then at the Remembrance Sunday service at the Cenotaph the following month, the King asked after them and even remembered their talent for maths.

The author added: “Clearly, you know, this was a pretty painful episode those 40, 50 days. But she said that actually the King was very charming. He’s a considerate monarch.”

Mr Hardman believes that the King “felt sympathy for a woman destined to go down in the history books for the shortest premiership in British politics”, as she was succeeded by Rishi Sunak in October 2022.

King Charles has already surpassed the shortest reign in British history, with that dubious honour belonging to Lady Jane Grey who was overthrown after just nine days on the throne and later executed.

King Charles does hold another record though for the longest tenure as Prince of Wales, at 64 years and 44 days, and was also heir apparent for longer than any other in British history.

This was due to the historic reign of his mother Queen Elizabeth II, the longest ever reigning British monarch who celebrated her Platinum Jubilee just three months before her death.

She became Queen upon the death of her father King George VI on February 6 1952, when she was just 25-years-old and she lived to be 96.