File photo: The princess speaks candidly and informally about her courtship with the Prince of Wales. Picture: AP

London - The broadcast of the controversial Diana documentary divided its British TV audience on Sunday night.

Channel 4 defied criticism to air private video recordings in which the princess revealed details of her sex life with Prince Charles.

The broadcaster had ignored a public outcry and criticism from those who accused it of paying "blood money" for the "deeply personal" recordings.

Although some of the tapes had previously been broadcast in America, it was the first time the footage was viewed by a British audience.

Many viewers went on Twitter to give their reaction, labelling Channel 4 "disrespectful", "intrusive" and "tacky."

One user said: "I can’t believe Channel 4 would have the nerve to make these Diana tapes public. They are being very disrespectful towards her memory."

But others said that despite not agreeing with the tapes being broadcast, they struggled to switch it off.

One said: "I’m a walking contradiction. I don’t agree with this being showing yet I’m so intrigued in watching it." Another wrote: "Feel like I’m overhearing a conversation I shouldn’t be listening to."

The documentary Diana: In Her Own Words is centred on tapes recorded by her speech coach, ex-Coronation Street actor Peter Settelen, during vocal coaching lessons between September 1992 and December 1993 at Kensington Palace.

The princess speaks candidly and informally about her courtship with the Prince of Wales, her troubled marriage and her "very odd" sex life.

Channel 4 has defended its decision to show the tapes by insisting that they are "matter of public record".

Those who watched the broadcast saw the princess making a number of revelations. Among them were:

First encounter with Charles

Diana says she had previously been "unimpressed" by Charles, but after meeting him at a polo match in Sussex when she was 18-and-a-half she thought: "I am quite impressed this time round." She adds: "He chatted me up, you know, he was like a bad rash, he was all over me, and I thought, you know, urgh, [pulls back, pulls face]."

After saying Charles needed someone by his side, she says he "leapt" on her. "He started kissing me and everything, and I thought, 'Urgh this is not what people do'." She adds: "And he was all over me for the rest of the evening, followed me around, everything, like a puppy. I was flattered but I was very puzzled."

Early days of courtship

The princess says Charles "wasn’t consistent with his courting abilities". She says: "He’d ring me up every day for a week and then he wouldn’t speak to me for three weeks; very odd. And I’d accepted that and I thought fine, well he knows where I am if he wants me. And then the thrill when he used to ring up was so immense and intense, drive the other three girls in my flat crazy. But no, it was all, it was odd."

Engagement

Diana reveals she had met Charles only 13 times before their wedding, before giggling nervously.

She adds: "I was brought up with the sense that when you get engaged to someone, you loved them."

Recalling an interview in 1981 after their engagement was announced which left her "traumatised", she tells voice coach Peter Settelen: "The most extraordinary thing is we had this ghastly interview the day we announced our engagement and this ridiculous ITN man said, 'Are you in love?'

"I thought what a thick question so I said, 'Yes, of course we are', in the sort of Sloane Ranger I was, and Charles turned round and said, 'Whatever in love means'. That threw me completely. I thought what a strange question and answer. God. Absolutely traumatised me."

Sex with Charles

She describes how she and Charles had sex "sort of once every three weeks" but their "odd, very odd" sex life "fizzled out" after Harry was born in 1984.

She says: "It was odd, very odd. But it was there, then it fizzled out about seven years ago, six years ago, well seven, because Harry was eight. Instinct told me, it was just so odd. I don’t know, there was no requirement for it from his case."

Charles and Prince Philip on the affair

Diana says that when she confronted Charles over his infidelity with Camilla, he replied: "I refuse to be the only Prince of Wales who never had a mistress." Recalling a conversation between Charles and his father in which the Duke of Edinburgh appeared to condone his affair, she says: "My father-in-law said to my husband, 'If your marriage doesn’t work out you can always go back to her after five years'."

Queen’s advice after Charles’s affair

Diana says she went sobbing to the Queen, who she referred to as "the top lady", to ask for advice about her failing marriage and Charles’s infidelity.

She says: "I asked her, 'What do I do? I’m coming to you, what do I do?' " – to which she said the Queen replied: "I don’t know what you should do, Charles is hopeless." The princess adds: "And that was it. That was help. So I didn’t go back to her again for help."

This August 31, 1997 photo by made available by HM Coroner shows Diana, left, with Dodi Al Fayed in the back of a car, on the night that both of them died in a car crash in Paris. Picture: AP

Bulimia

She blames the state of the marriage and her isolation in the Royal Family for her eating disorder.

"Everyone knew about the bulimia in the family and they all blamed the failure of the marriage on the bulimia. And that’s taken some time to get them thinking differently," she says.

She says that she told the Royal Family: "I was rejected, I didn’t think I was good enough for this family, so I took it out on myself.

"I could have gone to alcohol – which would have been obvious. I could have gone anorexic – which would have been even more obvious. I decided to do it more discreetly. Which ultimately wasn’t discreet. But I chose to hurt myself instead of hurting all of you."

Putting on a brave face in public

While behind palace doors the royal couple faced emotional struggles, Diana claims that when in public they were a "good team".

She says: "I used to get in the car with Charles and I used to blub in the car. There would be crowds everywhere and he would say, 'Now what’s the matter?' I said, 'I can’t be in this car'. He said, 'Why?' 'I can’t be in this car, I don’t feel safe'. I was neurotic almost but then when I got out of the car [pulls face of calm]."

‘Best time of my life’ living with friends

Diana says her happiest time was while living with three friends in a flat on Old Brompton Road in Chelsea while she was in her teens.

"I loved it, so happy there. I had three girls living with me and I had the best time of my life," she recalls.

Being rebellious

"I was a rebel, I always did the dares, I always did the opposite of everyone else. I wasn’t academically interested at all, I just wanted to be with people and have fun and look after people," she adds, rolling her eyes in self-parody. "But the rebel thing was always there. It was underlying. It didn’t come out. Or they didn’t see it."