SAO PAULO, Brazil, Oct 19, 2007 (AFP) - Lewis Hamilton, one of three drivers in with a shot of the world drivers title here this weekend, is facing a possible penalty after flouting a rule in Friday´s free practice session.

Hamilton, leading the championship by four points going into Sunday´s closing race at Interlagos, illegally used two sets of wet tyres tyres in the morning´s 90-minute session.

Arcticle 25.3 of the rule book states: "No driver may use more than one set of wet and one set of extreme wet tyres during P1 and P2."

The McLaren driver was not the only one to fall foul of the new regulation, both Honda´s Jenson Button and Super Aguri´s Tajuma Sato also used two sets of wets.

The three drivers have been summoned before the FIA after Friday´s second session.