Paparazzo Romuald Rat, one of the first at the scene of the crash which killed Princess Diana, may be summoned to give evidence at her inquest.

The court, however, is unclear about Mr Rat's whereabouts and it is not known whether he can be summoned to give evidence under French law.

Ian Burnett QC, counsel to the inquest, told coroner Lord Justice Scott Baker last week: "The position is that no one knows where he is at the moment and efforts are continuing to try to locate where he is."

Earlier, witness Georges Dauzonne told the jury by video link from the French capital that he was driving his Rolls-Royce across the bridge from the south side of the River Seine to join the expressway just after the Alma Tunnel at around half past midnight on August 31.

He told the court that as he went on to the slip road, he noticed a car driving erratically in front of him.

"I thought he was drunk," he told the court.

Mr Dauzonne described the car as in bad condition with a loud exhaust and said there was a large dog wearing a red bandana sitting in the back, with its head visible over the seats.

On seeing the car touching the white markings at the edge of the slip road, Mr Dauzonne slowed down to around 30kph (18mph), he told the court.

He then watched as the driver swerved across to the right then the left and then back again, almost stopping.

"I was almost stopped behind him trying to understand what he wanted to do and told my wife 'This guy must be drunk' and then I go on the left and I zoom on," he said.

But Mr Dauzonne said he did not see an accident further back in the tunnel or hear the sound of a collision.

The inquest,sitting at the High Court in London, is expected to hear from Stephane Darmon, the motorcyclist to paparazzo photographer Romuald Rat, also by video link.

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