"In open wheel racing, if you've won F1, there's nothing above it. I don't want to race just for the sake of racing. I've got other things in my life," the 1997 champion told Britain's weekly Autosport magazine in an interview.

"Le Mans could be a fun thing, because it's a special race to win, but that's the only reason for it. You can't make a career out of that, but you can do it until later anyway, so there's no rush.

"If I was going to drive again, it would have to be NASCAR, that's all," added the 35-year-old Canadian, who split with BMW Sauber last month.

"Of course, when you look at the cars they're big and heavy and it's different, but the races look very exciting, and there's a lot of talent in there.

"And basically it's something you have to learn from scratch, and I think that's what would make it interesting and exciting. When you start at the bottom of the ladder and have to learn, you really have to outdo yourself, it makes it exciting."

Colombian Juan Pablo Montoya has already left the Mclaren Formula One team for NASCAR.

Villeneuve said he quit BMW Sauber because he had not wanted to get involved in a 'shoot-out' with Polish test driver Robert Kubica for the 2007 race seat.

"After having been in F1 for 10 years and having won the championship and so on, even though it's quite a few years ago, I wasn't ready to stay home some weekends just to see how the other guy would go and to then be compared to him," he said.

"Not because I was worried that he would go faster or slower, it could happen both ways and that would be life," added the Canadian.

"It's just not something that anybody that's been there and won races would accept basically, that's all.

"I knew that after that I wouldn't be able to give everything I had. It just doesn't feel fair, so I wouldn't be able to train like a maniac and take all the risks that I took racing, basically."

Kubica, Poland's first Formula One driver, replaced Villeneuve at the Hungarian Grand Prix after the team said the Canadian was still recovering from a crash at the previous race.

That was subsequently revealed to have been a pretext, with the separation announced on the morning after the Hungarian Grand Prix and Kubica confirmed for the rest of the year.

BMW have yet to say who will partner Germany's Nick Heidfeld in 2007, although Kubica is the obvious choice.