Earl Spencer, the younger brother of the late Princess Diana, has hit back at the British royal family's denial of claims that King Charles III made harsh remarks about Diana following her death.

Appearing on BBC broadcasting on the 18th local time, Earl Spencer stated, "All I can say to you here and now is that he said precisely that," adding, "I am telling the truth."

According to excerpts released ahead of the publication of Earl Spencer's memoir, King Charles III, during a telephone call shortly after Diana's death in 1997 over disagreements regarding her funeral, snapped, "Don't worry, we'll soon forget her."

Shortly after the initial excerpts were made public, Buckingham Palace issued an unusually strong statement claiming that Earl Spencer's "judgment was clouded by grief, leading to distorted memories."

Asked about this statement, Earl Spencer retorted, "Is he angry, or is he embarrassed?", arguing that the royal palace blurred the essence of the matter by suggesting that "memories can differ."

Earl Spencer said, "In my entire life, I had only two phone conversations with him. I was listening very carefully to what he was saying, and those were his exact words," adding that because it was such a "monstrous" thing to say, he shared it with family and friends at the time.

In the excerpts of the memoir, Earl Spencer also wrote that he took several seconds to respond out of shock at King Charles III's words, telling him, "I can't believe you said that," before hanging up.

The memoir also details that when Earl Spencer objected that Diana would not have wanted her sons, Princes William and Harry, to walk behind the funeral procession, King Charles III lashed out at his former in-laws, saying, "That's your family's problem. You have not got an ounce of duty."

Buckingham Palace has not issued any additional statements following its statement released on the 16th.

(Photo: AP, Yonhap News)