A claim has been raised that Britain's King Charles III was as overjoyed upon hearing the news of the late Princess Diana's death as if he had won the lottery.

The BBC reported on the 17th (local time) that Earl Charles Spencer, Diana's younger brother, made the claim in his memoir.

In his book, Earl Spencer recalled the moment he received a phone call in the middle of the night on August 31, 1997, at his home in Cape Town, South Africa, informing him of Diana's death.

He claimed that immediately after receiving the news of Diana's death, he received a phone call from then-Prince Charles, and that his voice at the time sounded extremely excited.

Earl Spencer wrote, "Unlike others who were overwhelmed by shock and could barely express condolences or even find words to say, his voice was thrilled with joy, as if he had won the lottery," adding, "That is how I remember thinking at the time."

The memoir also contains details about Diana's troubled marriage.

Earl Spencer recalled hearing from a friend of Diana that the night before the wedding, King Charles III told Diana, "I am glad to get married, but I do not love you."

He added that the situation in the early days of the marriage must have been very difficult, and that "both of them must have viewed each other with desperation."

He also wrote that Diana considered taking her own life more than once during her later years, but endured out of love for her sons.

Earl Spencer previously stated that just before Diana's funeral, King Charles III told him in a phone call, "Don't worry, we will soon forget her."

In response, a Buckingham Palace spokesperson stated, "His Majesty is mindful that the grief of losing a sibling can cloud reason, affect judgment, and distort memory," adding, "Even many years after such a loss, one may remain unaware of such effects."

The statement implies that Earl Spencer's judgment was clouded by the grief of losing his sister.

A spokesperson for Prince Harry declined to comment on Earl Spencer's book.

Earl Spencer's book, "A Song for Swans: Diana, My Sister," is scheduled to be published simultaneously in the UK and the US on the 22nd.

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