LONDON — Mohammed Fayed accused the Duke of Edinburgh yesterday of being a “Nazi” and a “racist” who ordered MI6 to assassinate Diana, Princess of Wales because she was pregnant with a Muslim baby.

In a series of extraordinary allegations at the inquest into the princess’s death, Mr. Fayed also accused her former husband, the Prince of Wales, of plotting her “murder” so he could marry his new “crocodile wife,” Camilla Parker Bowles.

He said the royal family were a “Dracula family” who had murdered the princess the moment she had found happiness and even implicated Tony Blair, the former prime minister, in the plot.

The Harrods owner told the High Court hearing in London that he had fought a 10-year battle against a vast conspiracy encompassing both the British and French establishments as he tried to prove that the princess and his son, Dodi, were killed by MI6, on the orders of the duke, in a staged car crash in Paris on August 31, 1997.

The alleged conspiracy and cover-up included senior royals; MI6; two former Scotland Yard commissioners; French police and medics; the princess’s sister, Lady Sarah McCorquodale, and several of her close friends, he claimed.

At the center of Mr. Fayed’s case was a claim that his son and the princess telephoned him an hour before the accident to say they were expecting a baby and would announce their engagement after she had told her sons.

Mr. Fayed said, “I’m the only person that they told. Princess Diana told me before and during the holiday we shared in July 1997 of her fears. She told me that she knew Prince Philip and Prince Charles were trying to get rid of her.”

He went on, “Prince Philip would not accept my son or anyone who is a person of different religion, naturally-tanned, curly hair. They would not accept that he would have anything to do with the future King.

“Prince Philip rules the country behind the scenes. I think Prince Philip is the actual head of the royal family. He is a racist. He was brought up by his aunt who married one of Hitler’s generals.

“This is the man who is in charge, who is manipulating and can do anything. It’s time to send him back to Germany from where he comes. You want to know his original name — it ends in Frankenstein.”

Ian Burnett QC, for the coroner, asked Mr. Fayed, “All this stems from your belief that Prince Philip is not only a racist but a Nazi as well?” Mr. Fayed replied, “That’s right.”

Prince Philip was originally a member of the Danish-German House of Schleswig-Holstein-Sonderburg-Glucksburg and Mr. Fayed was thought to have been comparing that name with “Frankenstein.” The duke later changed his name to Mountbatten.

He claimed the murder was “executed” by a photographer, James Andanson, who has since died, in a white Fiat Uno and that Mr. Andanson was later “got rid of.”

He said Mr. Andanson was employed by MI6 and “pushed” the couple’s Mercedes as strobe lights were flashed to blind their driver, Henri Paul, who was also in the pay of MI6 but had been “duped” by them.

After the crash two French pathologists swapped Mr. Paul’s blood for that of someone else to show he was drunk, he alleged.

Mr. Fayed also claimed that Tony Blair, the former premier, was implicated in the plot. He believed the assassins were acting on orders from “the prime minister and his henchmen” as well as the royal family.

Mr Fayed said he was convinced there was a cover-up because of a note written by the Princess’s divorce lawyer, Lord Mishcon, following a 1995 meeting in which she said there was a plot to kill her in a staged car crash. The document was locked in a safe at Scotland Yard and only sent to the coroner in 2003.

Mr. Fayed said, “I cannot believe that they sat upon such an important note and did not pass it on.”

The inquest continues.