Princess Diana's Brother Makes Startling Claim About King Charles' Reaction to His Ex-Wife's Death in New Book

Princess Diana's brother is making a startling claim about King Charles III's reaction to his ex-wife's death.

In his forthcoming memoir, Swan Song: Diana, My Sister, Charles Spencer recalls speaking to the then-Prince Charles shortly after Diana died in a Paris car crash in August 1997. According to Spencer, the future king sounded "giddily elated, like a lottery winner" during the phone conversation.

Spencer, 62, writes that his phone was ringing constantly as news of his sister's death spread.

While he remembered other callers struggling to express their condolences, Spencer claims Charles' demeanor stood out.

"Unlike my other callers, who were stunned," Charles sounded "giddily elated," Spencer writes in the book.

The characterization reflects Spencer's recollection of the conversation nearly three decades later and has been disputed by Buckingham Palace.

During the call, Charles also told Spencer that he had broken the devastating news to Prince William and Prince Harry, who were just 15 and 12 years old at the time.

Spencer writes that Charles explained he had informed the boys in their bedrooms at Balmoral that morning.

To Spencer, the conversation sounded unusually "matter-of-fact" considering the magnitude of what had happened.

Spencer goes further in the memoir, offering his own theory about why he remembers Charles sounding that way.

Looking back, Spencer writes that he suspects Charles' initial reaction may have centered on how Diana's death could affect his future with Camilla Parker Bowles, whom Charles ultimately married in 2005.

Spencer's explanation is his personal interpretation of Charles' state of mind, rather than an independently established account of what the king was thinking at the time.

The alleged phone call isn't the only explosive interaction Spencer recounts.

In another excerpt from Swan Song, he describes arguing with Charles over whether William and Harry should walk behind their mother's coffin during her funeral procession.

Spencer says he strongly opposed having the young princes participate. During the heated exchange, he alleges Charles eventually told him, "Rest assured, we'll forget her soon enough!"

William and Harry ultimately joined their father, grandfather Prince Philip and Spencer in walking behind Diana's coffin at her September 6, 1997, funeral.

Buckingham Palace took the unusual step of responding to the allegations in Spencer's memoir.

While noting that the palace does not typically comment on books, a spokesperson said the king is conscious that intense grief can affect a person's "judgment" and "color memory" even many years later.

The statement did not provide an alternative account of the alleged conversations.

Swan Song: Diana, My Sister is scheduled to be released on September 22, ahead of the 30th anniversary of Diana's death in 2027.

Spencer previously described the memoir as the most personal of the 10 books he has written. After recording the audiobook, he said the project was, at its heart, a brother's tribute to his late sister and that he believed Diana would have approved of what he wrote.