Prince William has said he welcomes a new investigation into the BBC's 1995 Panorama interview with his mother, Princess Diana.
The independent inquiry will be led by Lord Dyson, a former Master of the Rolls and head of civil justice, and is to begin straight away.
The investigation will seek to discover how the corporation and journalist Martin Bashir got the television scoop.
In a statement, Kensington Palace said the Duke of Cambridge has tentatively welcomed the inquiry, saying: "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."
Revelations from the interview included Diana describing Camilla Parker Bowles as the "third person" in her marriage, her admission of infidelity with army captain James Hewitt, and her doubts over Prince Charles's suitability to be king.
Diana's TV appearance was watched by 23 million people at the time and sent shockwaves through the monarchy.
The steps that the interviewer, Bashir, took to obtain access to the Princess of Wales will be looked at as part of the probe.
There has been controversy over counterfeit bank statements which were alleged to have been used to persuade her to take part in the interview, since shortly after the programme first aired.
The documents are alleged to have been used to falsely show payments were made to members of royal staff in exchange for information about the princess.
Diana's younger brother Earl Spencer has said he was shown the documents and went on to connect his sister with Bashir - something the earl says he would not have done had he not been misled.
As well as demanding an independent inquiry, he has also requested a posthumous apology to his sister and a donation to charities set up in her memory.
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Just last week, a note written by Diana stating that false bank statements had no role in her decision to speak on camera was found by the BBC, which had initially said the handwritten letter was no longer in its possession.
The independent investigation will also look into an internal BBC inquiry in 1996 led by then head of news Tony Hall.
That inquiry is understood to have found that Bashir, who the BBC says is seriously unwell with COVID-19, had "done wrong", but it is not known what sanction, if any, he faced.
Speaking about the new investigation, director-general of the BBC Tim Davie said the corporation is "determined to get to the truth", calling Lord Dyson "an eminent and highly respected figure who will lead a thorough process".
Lord Dyson has said he will ensure the "important investigation" is "both thorough and fair".
Diana and Charles divorced in 1996 - the year after the interview, and the princess was killed in a car crash in Paris the following year.
The BBC will publish the report of the investigation at its conclusion.
Analysis: William clearly felt he had to make his views on the investigation known
By Rhiannon Mills, royal correspondent
This is a significant statement from the Duke of Cambridge. Until now Kensington Palace have had no comment to make when asked for his thoughts on the circumstances surrounding the Panorama documentary and the growing pressure on the BBC.
But this "tentative welcome" from Prince William for an independent investigation, and his description of it being a "step in the right direction", says a lot.
It is a public acknowledgement that he will be watching closely to see how the process unfolds and what findings the investigation eventually delivers.
Like Princess Diana's brother Earl Spencer, and many others, he wants to know if his mother was in some way tricked into doing the most explosive royal interview ever seen and whether there was a cover up at the BBC.
Yes, in the past Diana's sons have spoken about how their mother was hounded by the press, however they have often been cautious about engaging in stories about the princess.
But now Prince William has clearly felt he has to make his views on this investigation known, and add his important voice to those growing calls for the truth.
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