King Charles vowed Princess Diana would be forgotten ‘soon enough’ after death in fiery fight with her brother: memoir

King Charles III allegedly told Princess Diana’s brother that she would be forgotten “soon enough” in a horrific phone call following her death in 1997.

In the forthcoming memoir “Swan Song: Diana, My Sister,” Charles Spencer reflected on the monarch allegedly releasing his “pent-up contempt for Diana” after the Princess of Wales died in a Paris car crash, per the Daily Mail.

“He unleashed down the phone what I have always taken to be his pent-up contempt for Diana, and his horror that the world was so bowled over by her death,” Spencer claimed. “’Rest assured,’” he hissed, ‘we’ll forget her soon enough!’”

Spencer recalled his shock at Charles’ alleged remarks and being too “stunned” to respond.

“I can’t believe you just said that,” Spencer told Charles before hanging up the phone.

A rep for Buckingham Palace declined to comment to Page Six.

According to the outlet, Spencer’s book will also dive into Diana’s marriage and 1981 fairytale wedding at St Paul’s Cathedral in London.

The author also explores the exes’ failed marriage, including extramarital affairs leading up to their tumultuous divorce in 1996, one year before she died.

Spencer also wrote about Diana’s funeral at London’s Westminster Abbey on Sept. 6, 1997, and how he allegedly received a call days before from Queen Elizabeth’s aide, insisting that Diana and Charles’ sons, Prince William and Prince Harry, wouldn’t be participating in the procession.

“That’s not going to happen,” Spencer allegedly told the aides.

Sure enough, Harry and William joined Spencer, along with Charles and Prince Philip, during the funeral procession.

Spencer’s tell-all memoir will be released on Sept. 22.

This story is developing …