Nov.18 (GMM) The particularly slippery conditions suffered by drivers at the new Circuit of the Americas this weekend is caused by oil, not dust.

That is the claim of the authoritative German publication Auto Motor und Sport, which said Texas' colder-than-expected temperatures and too-hard Pirelli tyres are also contributing to the problem.

But the biggest factor: "The brand new asphalt is sweating oil," said the report.

Pedro De La Rosa, HRT Formula 1 Team Photo by: xpb.cc

"(Circuit designer) Hermann Tike told Charlie Whiting that it is the same type of asphalt as in India and Korea," added journalist Michael Schmidt.

Pedro de la Rosa does not agree: "The asphalt here is different," said the HRT driver.

Fernando Alonso claims the Austin track - "very smooth and not at all porous" - reminds him of Portimao in Portugal.

Schmidt said the Spaniard is right.

De la Rosa confirmed: "You can see the oil shimmering when you look at the track in the morning."