Princess Diana regretted her infamous Panorama interview due to the impact it had one her young sons – a close friend has claimed.

The late Lady Diana – who passed away aged 36 after being involved in a car crash in Paris in 1997 – raised eyebrows and inited gossip when she sat down to bare her soul to Martin Bashir on 60 minutes on Panorama in November 1995.

The explosive interview saw the Princess discuss romantic relationships away from her technically-still husband at the time Prince Charles, although they had split and were divorced soon after.

She also famously declared there were “three people” in her marriage – making reference to Prince Charles’ own life-long attraction to now wife Camilla, Duchess of Cornwall.

Princess Diana regretted upsetting her sons with her famous Panorama interview, a friend has claimed

And while an hour of footage was aired on the BBC, it is believed that 20 other minutes may have existed that were never aired, and that master tapes would reveal re-takes of some of Diana’s answers to questions.

As the documentary’s 25th anniversary approaches, close friend Richard Kay has claimed the late Princess kept original copies of the tapes for leverage, and also expressed one regret about the bombshell interview - that it upset sons Prince William and Harry.

Prince William was 13-years-old when the documentary aired, while Prince Harry was just 11-year-old.

Prince Charles and Lady Diana split in 1992 after 11 years of marriage

Richard Kay told the Daily Mail: “Some told me that Diana kept a tape of it herself, hiding it in a hat box in her dressing room in case she ever needed it as ammunition in the future.”

While he went on to give insight in to what then-BBC Director General, John Birt, made of the interview after viewing a screening of it – offering a possible explanation for the ‘missing 20 minutes’ of the interview.

Richard claims: “Birt also made some suggestions about how William and Harry might react to some of their mother's words. This might have been the moment when editing began.

Prince William was 13 and Prince Harry was 11 when Diana's Panorama interview aired

“There is little if anything in the finished film about her charity work and nothing at all about other senior members of the Royal Family, apart from Charles.”

Richard goes on to suggest some in Diana’s inner circle were horrified by her tell-all interview.

He claims: “close friends who she had not told were horrified by what she had done, fearing the damage it might do to her sons William and Harry.”

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Princess Diana regretted upsetting Prince William with her interview, a friend claims
Diana bared her soul to Martin Bashir on 60 Minutes on Panorama in November 1995

He also suggested the Princess was unconcerned by some suggesting she seemed “unbalanced” in her interview.

He said: “Diana scoffed at such talk, but in private moments she later told me she did regret elements of the interview: questioning Charles's suitability to be king and, especially, confessing her affair with copper-haired cavalry officer James Hewitt.

“She believed it was a strategic mistake because the public already believed she had had an affair with Hewitt anyway. What really hurt was that it upset the then 13-year-old Prince William.”