A report in the Times said doctors have called for an investigation into what they describe as subliminal tobacco advertising on Ferrari's Formula One cars.

It is claimed the red, white and black bar code on Ferrari's cars and overalls was aimed at linking viewers with the Marlboro brand. Philip Morris, the maker of Marlboro, backs Ferrari but is not able to have any direct branding because of the EU ban on tobacco advertising. The ten-year contract, which was signed in 2001, is believed to be worth around US$1 billion but Ferrari have always refused to disclose the figure.

John Britton, a Fellow of the Royal College of Physicians and director of its tobacco advisory group, told the Times: "The bar code looks like the bottom half of a packet of Marlboro cigarettes. I was stunned when I saw it. This is pushing at the limits. If you look at how the bar code has evolved over the last four years, it looks like creeping branding."

A spokesman for Ferrari told the newspaper: "The bar code is part of the livery of the car. It is not part of a subliminal advertising campaign." A spokesman for Philip Morris said the deal complied with the law.

Ferrari is the only F1 team with a tobacco brand in its formal title - Scuderia Ferrari Marlboro. Its official logo also features a bar code and its drivers wear overalls bearing the bar code next to the Ferrari logo.