Hasnat Khan said he warned Princess Diana to be "careful" around interviewer Martin Bashir

Princess Diana's former love, Hasnat Khan, is speaking out against the BBC, claiming that the royal was "manipulated" during her famous Panorama interview.

In November, the BBC was accused of faking documents to secure the interview, and now, Khan — a cardiologist whose relationship with Diana began in 1995 and ended shortly before her death in 1997 — claims interviewer Martin Bashir "exploited" Diana. 

"One of her most attractive qualities was her vulnerability. It was what endeared her to the public. I later realized that Martin picked on those vulnerabilities and exploited them," Khan, 62, told the Daily Mail.

"He was very persuasive with Diana. It was all about him being from the BBC, being respectable and very pious even. But he filled her head with rubbish," said Khan, who is famously private and has rarely spoken publicly about his relationship with Diana. 

Khan said that after talking with Bashir, Diana began to believe that Prince Charles was having an affair with her sons' nanny, Tiggy Legge-Bourke, and made her paranoid "with talk of bugs and phone-tapping." 

Hasnat Khan, Princess Diana
Hasnat Khan and Princess Diana
| Credit: Shutterstock; Jayne Fincher/Princess Diana Archive/Getty Images

After meeting Bashir in a pub with Diana, Khan said he told the royal to be "careful." 

"Almost from the word go, he started asking me the most direct personal questions about Diana and our relationship. Why didn't we get married? When were we going to get married? That kind of thing," he said. "There was something about Bashir I didn't like. I told her to be careful of him." 

"Of course I am not naïve. I knew that there was a part of Diana that wanted to give an interview but my question is if Martin Bashir had not been there persuading her, would she ever have done it?" Khan added.

Diana in the Panorama interview
Princess Diana during her Panorama interview
| Credit: Getty Images

Princess Diana's close friend Rosa Monckton — who chose Diana as a godmother for her daughter — previously told the Daily Mail that she believed the BBC interview contributed to the royal's untimely death.

Monckton wrote that the BBC interview "dishonestly achieved, probably changed the course of history," prompting Diana and Charles to begin divorce proceedings.

"Among those decisions was the fact that Diana lost her royal title," Monckton said. "Had she retained it, she would have still been in the embrace of the Royal Family when in Paris on August 31, 1997. And she would almost certainly not have been in the incapable hands of a speeding drunk driver employed by Mohamed Al-Fayed, who owned the Ritz Hotel where she and his son, Dodi, had dined."

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The Sunday Times reported in October that Panorama host Martin Bashir created fake bank statements before the November 1995 interview in an attempt to convince Diana's brother, Charles Spencer, to help negotiate an interview with the princess.

An internal investigation conducted in 1996 concluded that the faked papers had "no bearing" on the interview, PEOPLE previously reported.

Spencer then sent a scathing letter to the head of the BBC accusing the media outlet of "dishonesty."

"[The BBC] have yet to apologize for what truly matters here: the incredibly serious falsification of bank statements suggesting that Diana's closest confidants were spying on her for her enemies," Spencer said in a statement to PEOPLE on Nov. 3.

Diana was infamously candid in the interview with Bashir, and opened up about her struggle with bulimia, the breakdown of her marriage to Prince Charles, the pressures of wedding a future monarch and raising young sons. She died less than two years later at 36.

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The BBC announced in November that they hired former British Supreme Court Judge John Dyson, Lord Dyson to lead an independent investigation surrounding Diana's appearance on Panorama.

"The BBC is determined to get to the truth about these events and that is why we have commissioned an independent investigation," said Tim Davie, BBC Director-General. "Formerly Master of the Rolls and a Justice of the Supreme Court, Lord Dyson is an eminent and highly respected figure who will lead a thorough process."

Prince William called the investigation a "step in the right direction" in a statement previously obtained by PEOPLE.

Tentatively welcoming the investigation, the Duke of Cambridge said, "The independent investigation is a step in the right direction. It should help establish the truth behind the actions that led to the Panorama interview and subsequent decisions taken by those in the BBC at the time."