Mohamed al Fayed was interviewed under caution by police in England today in connection with an allegation of sexual assault against a girl under 16, sources said.
The Harrods owner voluntarily went to a police station in west London this morning to answer questions about the alleged incident in May.
Scotland Yard refused to confirm that Mr al Fayed had been questioned.
A Metropolitan Police spokeswoman said: “We can confirm that a man attended a west London police station by prior arrangement and was questioned under caution this morning.
“The man was questioned in relation to an allegation of sexual assault on a girl under 16 at a business premises in central London.
“The allegation was received in May 2008.”
The Met’s Operation Sapphire, which investigates sexual offences across London, is leading the inquiry.
There have been no arrests so far.
A 15-year-old girl accused a senior Harrods executive of sexually assaulting her at the Knightsbridge store in May, the 'Mail on Sunday' reported earlier this year.
The teenager, who cannot be named for legal reasons, told police she was kissed by a male executive after meeting him while shopping with her mother, according to the paper.