The Italian news agency ANSA, citing judicial sources, said the action stemmed from the recent Monaco Grand Prix. Six days before that race an unidentified power was allegedly found on the fuel tanks of drivers Felipe Massa and Kimmi Raikkonen.

Ferrari didn't comment on the suit but said that Stepney remains an employee of Ferrari but disciplinary proceedings have been brought against him, ANSA said.

The report claimed that Stepney was unhappy since his immediate supervisor, Ross Brawn, left the company last year. Stepney has been moved from the race team and to the performance development team. He reportedly told a British interviewere views that move a demotion.