Charles Spencer has apologised to Piers Morgan for an "inaccuracy" in his new memoir about Princess Diana.
The Earl's book Swan Song: Diana, My Sister finally hit shelves on Tuesday after causing a storm in the weeks leading up to its publication, including claims that King Charles said "we'll forget her soon enough" after his ex-wife died in 1997.
The situation escalated on Tuesday morning when broadcaster Piers Morgan threatened to sue the Earl over "fabricated inaccuracies" in his book.
Writing on X, formerly Twitter, he said: "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'."
© Instagram / @charles.earl.spencerThe passage in question accused Piers and a fellow Mirror journalist of publishing pictures taken of Diana with "hidden cameras" in 1993.
However, the apology acknowledged that Piers did not join the Mirror until 1995.
After receiving the apology, Piers said he would continue to pursue legal action "against him and his publisher Penguin to have the lies removed, and damages paid to the King's Trust".
Speaking on his Uncensored show, he called the passage "very damning" and said he had been described "in the most despicable manner imaginable".
What did Earl Spencer write about Piers Morgan?
In the passage, Diana's brother said he was "flabbergasted" that newspaper editors, including Piers, had been invited to his sister's funeral.
Robert Fellowes, the senior private secretary to the Queen, then called the journalists to tell them they were "uninvited".
© JORAS/GC ImagesAccording to a passage read out by Piers, Charles Spencer wrote: "They realised they were unable to be rude to the brother of the much-mourned Princess… 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.
"I assumed Morgan must be feeling particular guilt because, 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.
"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."
Earl Spencer's apology to Piers Morgan in full
In a statement released on Tuesday, the Earl apologised to Piers for an incorrect assumption about his time as editor of The Mirror, but maintained the account of their phone call was "accurate".
He said: "Earl Spencer's account of his conversation with Piers Morgan is accurate.
"Mr Morgan was surly and annoyed when Earl Spencer called personally to tell him that he was not welcome at his sister's funeral.
© Tim Graham Photo Library via Get"The book then records Earl Spencer's assumption that Mr Morgan's response was because he was editor of the Daily Mirror when the Mirror Group had published highly intrusive photographs of Princess Diana at the gym.
"The photographs were published by the Sunday Mirror on 7 November 1993.
"Mr Morgan has pointed out that he did not join the Daily Mirror until October 1995. As an historian, accuracy is important to Earl Spencer.
"He therefore wishes to clarify that his assumption was incorrect. Earl Spencer apologises to Mr Morgan for this error."
