Scotland Yard will not investigate BBC journalist Martin Bashir over the 1995 interview with Princess Diana.
Bashir was accused of using dishonest tactics – including forging documents and misleading family members – to gain access to the former royal ahead of a bombshell TV documentary.
The campaign was led by Diana's brother Earl Spencer, who claimed Bashir repeatedly deceived him in attempt to speak to Diana as her marriage to Prince Charles broke down.
The BBC responded by pledging to hold a full independent investigation into the events leading up to the now infamous chat between Bashir and the late Princess of Wales.
A spokesperson for Scotland has confirmed today they will not be pursuing any criminal investigation following the allegations.
Martin Bashir obtained a career-defining interview with Princess Diana as her marriage to Prince Charles collapsed
Last year, the BBC journalist was accused of using dishonest tactics to gain access to Diana
Meghan Markle accuses Royals of 'perpetuating falsehoods' in tell-all Oprah clip
Commander Alex Murphy said: "In recent months the Metropolitan Police Service received correspondence alleging unlawful activity in connection with a documentary broadcast in 1995.
"This was carefully assessed by specialist detectives.
"They obtained legal advice from Metropolitan Police lawyers, independent counsel and from the Crown Prosecution Service.
"Following this detailed assessment and in view of the advice we received, we have determined that it is not appropriate to being a criminal investigation into these allegations. No further action will be taken," they confirmed.
"In this matter, as in any other, should any significant new evidence come to light we will assess it," they added.
It was during Bashir's explosive interview, which aired 25 years ago, that Diana uttered the famous words: "Well, there were three of us in this marriage, so it was a bit crowded."
Following the allegations that surfaced against Bashir last year, Prince William spoke out to say he 'welcomed' the BBC's investigation.
The Duke of Cambridge called the inquiry 'a step in the right direction' and said he hoped that the truth about the infamous Panorama interview between Princess Diana and journalist Martin Bashir would out.
In a statement released via Kensington Palace, Prince William 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."
This Sunday, Diana's youngest child Prince Harry will appear with his wife in a similar 'tell-all' interview with American chat show host Oprah Winfrey.
Prince Harry and Meghan Markles's interview will air this Sunday night in the US
A teaser for the eagerly anticipated chat – which airs on ITV on Monday night – sees Harry explain his fear of 'history repeating itself' with Meghan, in a reference to his later mother being pursued by paparazzi.
"It's been unbelievably tough for the two of us but at least we have each other," Harry said.
Mirror Online has contacted the BBC for comment.
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