British police said Tuesday they found "no credible evidence" that Diana, princess of Wales was murdered by special forces, following a probe into the new claims over her death in 1997.
Scotland Yard announced in August it was checking recently received information about the deaths of the princess and her boyfriend Dodi Fayed, including an allegation that she was killed by Britain's elite Special Air Service (SAS).
Diana and Fayed were killed in a car crash in a Paris underpass in the early hours of August 31, 1997, along with their French driver Henri Paul.
The Metropolitan Police Service (MPS) conducted a "scoping exercise" to assess its relevance and decide whether it warranted a new criminal investigation.
"The final conclusion is that whilst there is a possibility the alleged comments in relation to the SAS's involvement in the deaths may have been made, there is no credible evidence to support a theory that such claims had any basis in fact," said the police statement.
"Therefore the MPS are satisfied there is no evidential basis upon which to open any criminal investigation," it added.
It is understood the new claim was made by the former parents-in-law of an ex-soldier, based on information he had talked about in the past.
The allegations were widely covered in parts of Britain's tabloid press.
"Every reasonable line of enquiry was objectively pursued in order to fully evaluate any potential evidence," Scotland Yard said in a statement.
The numerous conspiracy theories surrounding the crash were investigated several years ago by John Stevens, formerly Britain's top policeman.
His two-year inquiry, Operation Paget, concluded in 2006 that all the allegations it assessed were without foundation.
It rejected the murder claims voiced by some, including Fayed's father, Mohamed Al-Fayed.
The Egyptian tycoon's lawyer Simon McKay branded the scoping exercise "the latest whitewash in a 16-year cover-up" over the deaths.
"The Met should never have been given charge of the case as they had every incentive to return the result we now see. To have done anything else would have called into serious question their own Paget Report," he said.
"Mr Al-Fayed will continue his fight to establish the truth that they were murdered and is convinced he will succeed in doing so."
Dodi Fayed, 42, and driver Paul -- the deputy head of security at Al-Fayed's plush Hotel Ritz in Paris -- were pronounced dead at the scene of the crash.
The Mercedes-Benz car had smashed into a pillar and spun around.
Diana, 36, the ex-wife of Prince Charles, the heir to the British throne, and the mother of Princes William and Harry, died later in hospital.
Bodyguard Trevor Rees-Jones, a member of the Al-Fayed family's protection team, survived.
Seeking to outrun chasing paparazzi photographers, Paul was found to have been speeding. His blood alcohol level was found to have been more than three times the French limit.
Diana married Charles in 1981 but their shaky marriage fell apart soon after Harry's birth in 1984, with both sides admitting adultery. They separated in 1992 and divorced in 1996.