The controversial book written by Princess Diana’s brother has hit the shelves, despite British commentator Piers Morgan demanding the removal of several pages and damages for details he says are “bulls–t”.

Morgan, a former British tabloid editor, said he would sue over “demonstrable lies” in the book by Diana’s brother, Charles Spencer.

Swan Song was published in Britain by Penguin Random House early on Tuesday (local time).

“I am taking legal action against Earl Spencer and his publishers over demonstrable lies he has written about me in his new book, which call into question his credibility as a supposed ‘historian’,” Morgan wrote on X.

On Monday, on his TV show Piers Morgan Uncensored, Morgan went further.

“If Earl Spencer can be so incredibly defamatorily wrong about such basic facts involving me, well why should we believe anything else that he puts in this book?” he said.

Among the allegations are that Morgan “snarled with annoyance” when Spencer asked him not to attend Diana’s 1997 funeral. He was then editor of the Daily Mirror, and had been invited along with other newspaper bosses.

Spencer writes that he was “flabbergasted” at the invitations. He says he personally phoned each editor asking them not to attend, blaming the tabloids for years of intrusion into Diana’s life.

Most were “slightly confused”, but agreed not to attend the service at Westminster Abbey.

“The only one who sounded surly, as opposed to merely confused or embarrassed, was Piers Morgan of the Mirror, who snarled with annoyance before he hung up,” he wrote.

Spencer specifically accuses Morgan for being Mirror editor when it published photographs in 1993 of Diana working out in a gym.

“Four years earlier, he and his Sunday Mirror counterpart had published photographs taken with hidden cameras by a gym owner. They were of Diana working out in a leotard,” he writes.

“This was such an intolerable invasion of her privacy that Diana instructed lawyers to sue the Mirror Group and to block further use of the images.”

Morgan said that was “very damning, particularly about me”.

“There’s just one problem. It’s all bulls–t. And very, very easy bulls–t for me to prove it. The photographs which he says that I published were printed by the Sunday Mirror on November the 7th, 1993,” he said.

“I joined the Daily Mirror in October 1995. In fact, at the time of the gym pictures, I was doing a showbiz column on the Mirror’s arch-rival, The Sun, about as far removed from responsibility for the Mirror scoop as I could possibly have been.”

Morgan accuses Spencer of choosing “profit over principle”.

“A book which rails against the media’s invasion of royal privacy, has managed to invade royal privacy in the most grotesque way imaginable. Private conversations with the King in a moment of unimaginable grief and shock, which allegedly happened almost 30 years ago, are reproduced without context or response,” he said.

“The King, says Spencer, sounded giddily elated, like a lottery winner after Diana’s death and the most damaging allegation of all, that he told her brother, we will forget her soon enough.

“Readers, who will include [Diana’s sons] Prince William and Harry, are left with the unmistakeable impression that their father, our King, is a callous and uncaring ogre.”

Morgan is seeking damages from Spencer and Penguin Random House. He said he would donate any money to the King’s Trust.

“After all, to quote somebody, you can’t dish it out without getting it in return, right?” he said.

Last week, a Buckingham Palace spokesman said the King was “mindful that the pain of fraternal grief can cloud reason, affect judgment and colour memory in ways others do not recognise”.

There have been no official comments from Prince William or Prince Harry. But Spencer believes that at least one of the royal brothers is “completely fine” with the book.

“I can say that Harry is completely fine about it,” Spencer told People magazine.

“He said, I hope there’s nothing embarrassing about him in it. I said, ‘There isn’t’.

“It’s natural that people so in the public eye are concerned how they will come across in the book.

“But I could reassure both of them that they’re of course in the book, but really as examples of two little boys who had the most exceptional mother. I’m not in any way compromising their privacy at all.”

It comes amid reports that Harry – who spent part of his summer holiday with wife Meghan Markle and their children at Spencer’s country estate – is planning a documentary about Diana for the 30th anniversary of her death next year.

Britain’s Telegraph reports the Duke of Sussex wants to honour his mother’s legacy “in the most meaningful way”. It said he had approached Diana’s friends and relatives, including Spencer, to ask whether they would participate in a documentary.

In his book, Spencer writes that he chose to write it instead of speaking in one of the many planned productions about his sister.

He has also admitted to “concern” about how William and Harry would feel about his portrayal of their father, but added he is “not here” to write a “scandalous book” about the King. He told People he did “not really” have any fear about writing so candidly about the monarch.

“I’m not interested in who people are in terms of status,” he said.

“I’m looking at them as people. And the central person, the only one that really matters, is Diana.”

Spencer believes his sister would have liked the book.

“She always loved it when I paid compliments, and this is 350 pages of compliments,” he said.

-with AAP