Royal Vengeance is set to be released by US publisher Trine Day in January next year. In it, writer Sarah Whalen claims Diana was “gravely injured in a deliberate car wreck” and “allowed to slowly bleed to death” in the Pont de l’Alma road tunnel in Paris, France. Ms Whalen claims Diana followed in the footsteps of “many royal women” – including Henry VIII’s wives Anne Boleyn and Catherine Howard – killed as part of a “ancient cult ritual” which saw them executed. Appearing on the Conspiracy Show podcast, she said: “English power has always been a combination of battles. This is especially true with women…

Ms Whalen also claims the Princess of Wales had “a series of accidents” with her cars in the run-up to her death, claiming this as evidence she was being targeted. Egyptian businessman Mohamed Al-Fayed, whose son Dodi died alongside his lover Diana in the crash, has propagated numerous conspiracy theories over the years.