The intimate details were recorded during sessions with a voice coach who was helping the late princess with her public speaking skills.
Once-secret recordings of Princess Diana that reveal the most intimate details of her life will be broadcast in a controversial new documentary.
The tapes, in which Diana talks about her sex life with Prince Charles, were recorded in 1992 as she spoke with a British actor named Peter Settelen, who was hired to improve her public speaking skills.
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Parts of the tapes were broadcast by NBC in 2004, but were considered so sensational that they never aired on British TV. However, they will now be featured in an upcoming documentary on Britain's Channel 4.
Settelen convinced Diana to speak candidly about her private life in an attempt to reach into her personal experiences to learn to communicate with people from the heart.
"My parents — they never said they loved me," she says in the tapes. "There was no hugs or anything like that."
In the recordings, she also spoke about her first kiss with Prince Charles.
"He leapt upon me," she recalled, "started kissing me and everything and I thought, 'Wah! You know, this is not what people do!' And he was all over me for the rest of the evening, followed me around, everything."
Settelen asked, "There's virtually no sexual relations between the two of you?"
"There was. There was. There was," she replied. "But it was very odd. Very odd. But there was. It was there and then it fizzled out about seven years ago."
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She added: "There was never a requirement for it in his case. Sort of once every three weeks."
Television executives say they decided it was time to broadcast the tapes after Diana's sons, William and Harry, opened the door to her private life by participating in Diana, Our Mother: Her Life and Legacy, which aired Monday on HBO.
The tapes are raising eyebrows, according to royal expert Victoria Arbiter.
"I think the most shocking information is that she gets incredibly personal about her relationship with Charles," Arbiter told Inside Edition. "People that have seen the tapes say they are very intimate, very private. It's information that really no one would want in the public domain."
There's anticipation about how the royal family will react.
"I think the Queen, in her way, she's rather tight-lipped but I think she'll be furious, because yet again the monarchy is being dragged into a mire," Arbiter said.
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