Klein claimed that in the summer of 1997 he had received a phone call from Dodi al Fayed telling him for the first time that he and Diana were going to be in Paris at the end of that month.

"He (Dodi) must have been in Monte Carlo," recalled Klein. "I remember very well, he called me and he said 'Frank I just passed by a jewellers' shop' - he pointed out it was Van Cleef - he said 'I want to buy some jewellery, I'm going to get engaged'."

According to Klein, in a second conversation on August 29, Dodi told him he was going to Paris the next day.

"He did not mention the princess by name but he did tell me that he was going to stay in Paris, to live. He told me he was going to move to the Villa Windsor with his girlfriend, and he told me that they were going to get married."

Also Klein was the man who called Dodi's father, Mohammed al Fayed, in London, to tell him the news of the crash in the early hours of August 31.

"I said Mr Fayed, very sorry to disturb you, there has been a terrible accident. ... Dodi passed away and the driver, and Mr Fayed said 'sorry'," he recalled. "Mr Fayed said 'What about the princess?' and I said 'the information I have is she's alive' the only thing I knew, and I said 'an accident', that I said definitely”, Klein recalled.

From the moment he heard about the crash, Mohammed al Fayed was convinced the crash was an assassination or the result of a plot.

“Mr Fayed, very calm, said to me: 'Frank, this is not an accident, this is a plot or an assassination'.", Klein remembered.

When Klein replied that all that was known so far was that it was an accident, al-Fayed said: "Frank I know more than you know, more than you think."

Yesterday, Sebastien Dorzee, the first member of the emergency services to reach in the Pont de l'Alma tunnel, on August 31, 1997, revealed that Princess Diana saw her lover Dodi al Fayed dying in front of her.

"She moved, her eyes were open, speaking to me in a foreign language. I think that she said 'My God', on seeing her boyfriend dying. At the same time she was rubbing her stomach, she must have been in pain," Dorzee said. "A few seconds later she looked at me. Then she put her head down again and closed her eyes.”

Her lover Dodi al-Fayed, 42, and driver Henri Paul died on the spot, after their limousine crashed into a pillar in the Alma tunnel in Paris. They were trying to flee paparazzi, who had been pursuing them from the Ritz Hotel. The only survivor was bodyguard Trevor Rees.

Earlier this week, Robert Chapman, the pathologist who examined the body of Princess Diana, said that there were no physical signs of pregnancy at the time.

Chapman said that chemicals used in the embalmment of Diana's body in a Paris hospital hours after her death "could cause some changes such as blood clots."

But the embalming fluids would not affect the physical evidence of a pregnancy in an inspection of the womb or ovaries, he added.