MOHAMED Al-FAYED has reopened his battle with the royal family by putting £3m towards a documentary which resurrects claims about the Nazi links of the Duke of Edinburgh's relatives.

The film also includes allegations that the inquest into the deaths of Princess Diana and Fayed's son Dodi was fixed and marred by corruption.

There Are Dark Forces, which takes its title from a remark allegedly made by the Queen to the former royal servant Paul Burrell, is directed by the actor and comedian Keith Alen, father of the singer Lily and a longstanding friend of Fayed.

The film is nearly finished and 20 minutes of the £8m production was shown amid great secrecy yesterday at the Cannes Film Festival to a few selected American journalists. Lawyers for the film decided it was too "potentially seditious" to be seen by the British press.

It will be seen as yet another attempt by Fayed to discredit the royals — who he has called "that Dracula family" — and what he sees as a plot by the British establishment.

One contentious sequence in the film is footage of the teenaged Duke of Edinburgh at the funeral of his elder sister Cecile, in Germany in 1937.

Philip is seen walking behind the coffin surrounded by mourners in Nazi uniforms. There are also pictures of him at social events in Germany before the war where he is seen with Nazis in brownshirt uniforms.

The photographs, some previously unseen, were acquired from a German archive.

Philip went on to serve with distinction in the Royal Navy in the second world war.

The film slides from footage of the young Philip to still photos of Prince Harry taken three years ago in a Nazi uniform at a fancy dress party. The implication appears to be that there is a thread of association with Nazism running through some of the royal family.

The inquests into the deaths of Diana and Fayed's son Dodi concluded last month with verdicts that there was no attempt to murder them. Despite his earlier conspiracy theories, Fayed said afterwards that he accepted the verdict, but the new film depicts the inquest as a fix.

Allen, who is also the father of the singer Lily, made a Channel 4 documentary about the owner of Harrods in 2005. Both men support Fulham football club, which Fayed owns. Allen, like Fayed, has said in the past he does not believe Diana's death was an accident. Allen, who narrates and appears in the film, asserts that the British media has made up its mind about Diana's death before the inquest. He interviews al Fayed himself as well as the American writer Kitty Kelly, who wrote a book on the Royals, Howard Stern the controversial American broadcaster, and actor Tony Curtis who was the friend of Dodi Fayed. All are sympathetic to the notion that Diana was in some way murdered.

The film, which was researched during the inquest by the reporter Richard Wiseman, is critical of some of the behaviour of the British Press.

The film recreates a scene where the BBC's royal correspondent Nicholas Witchell apparently falls asleep during the inquest, which, according to the film, he did quite regularly.

Production notes for the film, which is looking for an American distributor at Cannes says that the Queen herself is "a corrupting force in British society" and that the documentary has examined the inquiry and found it wanting." It is, as it were, says the production notes "an antidote to the 2006 film The Queen".

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