Prince Charles and Princess Diana's relationship started as a fairytale: a romance fiction came to life witnessed by millions of royal fans around the world. But people also know that their marriage ended in the most unromantic way. 

Back in 1994, the then 45-year-old Prince of Wales received a stern warning before finally breaking his silence on the cheating allegations against the so-called "People's Princess."

In the hopes to put an end to the speculations, in June 1994, Prince Charles sat down for an interview with British journalist Jonathan Dimbleby. The two-and-a-half TV documentary aimed to discuss Charles' personal life up close and personal. 

When the journalist asked if he tried to be faithful and honorable when he married Lady Diana Spencer in 1981, Charles replied with: "Yes, absolutely!"

But in just one snap, public opinion about the heir to the throne changed quickly when he confessed: "Until it became irretrievably broken down, us both having tried."

When asked about the girl he cheated on with Diana, Prince Charles tried to downplay their relationship and said: "Ms (Camilla) Parker Bowles is a great friend of mine, I have a large number of friends that I'm terribly lucky to have."

"So many friends who I think are wonderful, and make a huge difference to my life which would be intolerable otherwise. She has been a friend for a very long time," he added.

Camilla was then Charles' ex-girlfriend, whom she dated before meeting and marrying Diana. 

The Warning

It was the first time that Charles publicly admitted that he had been unfaithful to Diana, leading people to question his abilities to take on the British throne. 

Unknown to many though, before the bombshell interview, the Prince was given a warning not to lie about anything as it would only result to the worst-case scenario.

Speaking to Channel 5's documentary "Charles and Camilla: King and Queen in Waiting," Charles' former press secretary Dickie Arbiter said that he was the one who gave a blunt warning to the Prince.  

"I warned them at the time it would have to be warts and all," Arbiter revealed.

"' You cannot deny anything, you cannot leave anything out. And nothing was left out,'" he said recalling what he told Prince Charles. 

The former press secretary also revealed that the Prince of Wales was very upset with all the negative press after the said interview. 

Diana's Side Of The Story

A year after Prince Charles' bombshell interview, it was Diana's turn to have a tell-all discussion with Martin Bashir.

During her hour-long one-on-one interview, Diana revealed that she was aware of Charles' infidelity, but she pointed out she was not in the position to do anything about it.

The mother-of-two admitted that she always knew that Charles was still in love with Camila. When asked if she thinks their affair led to their marriage falling apart, Diana said: "There were three of us in this marriage, so it was a bit crowded."

Arbiter revealed she spoke to Diana after the interview and claimed that the estranged Princess regretted what she has said. 

Diana and Charles divorced in 1995, two years before the tragic death of the Princess of Wales. 

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