Earl Spencer has accused King Charles of gaslighting him and being "astonishingly provocative" in the latest escalation of his row with the royals.
The earl has made a series of claims about the King in his new book - alleging he said "we’ll forget her soon enough" during a row over funeral arrangements for his sister Princess Diana.
Buckingham Palace said in response that "fraternal grief can cloud reason, affect judgment and colour memory in ways others do not recognise".
The earl has stood by his comments in several interviews, in which he also likened the media’s treatment of Prince Harry and Meghan to what Diana went through.
In his BBC interview, Earl Spencer also claimed:

In an interview in The Mail on Sunday, Earl Spencer hit out at the Palace’s response to his claims, telling the paper: "It is not every day you wake up to find you’ve been gaslit by the King.
"It was astonishingly provocative and below the belt because it was essentially trying to say I’d lied without the King being able to deny what I’d said.
"I also thought it was a rather poor imitation of the ’recollections may vary’ quote, which was a much more elegant way of putting things, but in these circumstances entirely out of place."
He also said Diana "would be cheering from the rafters at this book".
The earl made the allegations in Swan Song: Diana, My Sister, which is being serialised in the Daily Mail and is due to be published next week.
Harry and Meghan ’being destroyed daily’
In his BBC interview, the earl was asked if he thought Diana would "identify" with how Prince Harry and Meghan have been treated by the media.
"If you look at an article in a tabloid about Diana or the couple that you were mentioning, Harry and Meghan, you know, they can be really, really unpleasant," he told the BBC.
"And I think it would be really beholden on people to learn from Diana’s example."

The earl added: "I’m not here to speak for Harry and Meghan, but for anyone who’s being destroyed in this way daily, it must be such a cancerous influence in their life."
He said Diana was "really brought low" by her treatment by the media, and it was a "pity" to see "echoes of that" in the coverage of Prince Harry and his wife.
The earl has insisted he is telling the truth about the King and accurately remembers what was said at the time.
He told the BBC: "I told friends and family straight away, close friends and family, about what had been said, because it was so monstrous."
The King allegedly made the remarks about forgetting Diana during a row over whether William and Harry should follow the funeral cortege.
Earl Spencer walked behind Diana’s coffin alongside her sons, Charles, and the late Duke of Edinburgh.
The earl said his book is his "final word and celebration" of Diana and he’s now "done" with speaking publicly about that time.

Despite intense coverage of the earl’s claims, the Royal Family has been carrying on as usual.
On Saturday, Camilla was at Chatsworth House in Derbyshire for a festival for The Queen’s Reading Room, a charity she founded atter the success of her book club during the pandemic.
The Queen told people books have a "life-enhancing power" and being at Chatsworth, which has a library of over 17,000 books, was "like coming home".

Technology & Business Editor