Detectives in Britain are refusing to comment on a report that senior officers have doubts over the authenticity of a blood sample used in the French inquiry into the death of Diana, Princess of Wales.
The sample of blood said to belong to chauffeur, Mr Henri Paul - who died along with Princess Diana and Mr Dodi Fayed in a car crash in Paris in 1997 - is reported to be subject of "high-level concerns" in Scotland Yard.
The Timesnewspaper said detectives were questioning the blood specimen because French police had not carried out a DNA test which would prove it came from Mr Paul.
Doubts over the validity of the sample would undermine the credibility of the French inquiry, which concluded Mr Paul was driving under the influence of alcohol and drugs, lost control of the Mercedes car while speeding in the Pont D'Alma tunnel.
Mr Paul's family and Mr Fayed's father, tycoon Mr Mohamed al Fayed, have repeatedly drawn attention to the level of carbon monoxide in Mr Paul's sample, which was said to be so high he would have struggled to walk let alone drive a car.
Police Inspector Jean-Claude Mules, who played a central role in the French investigation, told The Times: "There was no error over the blood. We are very serious people and no errors are allowed."
Inquests into the deaths of Diana and Dodi were opened and adjourned earlier this week by royal coroner Mr Michael Burgess.
He asked Metropolitan Police Commissioner Sir John Stevens to investigate speculation that the deaths were not the result of a "straightforward, road traffic accident".
PA