Martin Bashir used “deceitful methods” to secure that controversial 1995 BBC “Panorama” interview with Princess Diana, a report is expected to find Thursday.

Bashir, who has now quit his post as BBC religion editor due to ill health, has been under investigation amid complaints from Diana’s brother, Earl Spencer, in which he claimed she had been tricked into taking part with the use of forged documents.

The probe began in November, after Spencer went public with notes taken during a meeting with Bashir and his sister.

The Telegraph reported ahead of the BBC inquiry’s findings that Bashir had “deployed deceitful methods in a breach of BBC editorial rules to secure his interview with Diana”, an official inquiry was said to have concluded.

The report, which was compiled by former High Court judge Lord John Dyson, allegedly claimed Bashir had breached guidelines by creating two false bank statements to improperly manipulate Diana into giving the interview, People reported.

The Telegraph was also said to have stated the six-month inquiry was further expected to slam senior BBC executives over allegations of a cover-up.

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“The use of deceit in making factual programs would have been permissible only in the case of investigating serious crime… and where prima facie evidence of the guilt of that person being investigated had already been obtained,” Richard Ayre, the BBC’s controller of editorial policy in 1995, told the Telegraph Thursday.

“Those circumstances clearly don’t apply to an interview with the Princess of Wales. It would not have been acceptable to use significant deceit in this case.”

The BBC has since apologized, with Director-General Tim Davie saying: “Although the report states that Diana, Princess of Wales, was keen on the idea of an interview with the BBC, it is clear that the process for securing the interview fell far short of what audiences have a right to expect. We are very sorry for this,” Deadline reported.

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Diana, who died in a Paris car crash in 1997, made her first public comments about her doomed marriage to Prince Charles during the controversial interview.

Ahead of the inquiry findings’ release, Earl Spencer took to Twitter to post:

Former Director-General of the BBC, Lord Tony Hall, then said he accepted the 1996 BBC inquiry into how “Panorama” secured its interview with Diana “fell well short of what was required,” adding he was “wrong to give Martin Bashir the benefit of the doubt.”

Bashir also released a statement regarding the report, saying, according to the Evening Standard: “This is the second time that I have willingly fully co-operated with an investigation into events more than 25 years ago.

“I apologized then, and I do so again now, over the fact that I asked for bank statements to be mocked up. It was a stupid thing to do and was an action I deeply regret.

“But I absolutely stand by the evidence I gave a quarter of a century ago, and again more recently.

“I also reiterate that the bank statements had no bearing whatsoever on the personal choice by Princess Diana to take part in the interview.”

He continued, “Evidence handed to the inquiry in her own handwriting (and published alongside the report today) unequivocally confirms this, and other compelling evidence presented to Lord Dyson reinforces it.

“In fact, despite his other findings, Lord Dyson himself in any event accepts that the princess would probably have agreed to be interviewed without what he describes as my ‘intervention’.

“It is saddening that this single issue has been allowed to overshadow the princess’ brave decision to tell her story, to courageously talk through the difficulties she faced, and, to help address the silence and stigma that surrounded mental health issues all those years ago.

“She led the way in addressing so many of these issues and that’s why I will always remain immensely proud of that interview.”

The BBC has since written to Prince William to apologize for the interview with his mother.