Williams driver Alex Wurz of Austria announced his immediate retirement from Formula One on Monday and said that he would not be taking part in the season's final race in Brazil [Images].

"I would like to announce my retirement from active racing in Formula One," Wurz, 33, said in a statement on his web site (www.alexwurz.com). He finished 12th on Sunday at the Chinese Grand Prix.

"In such a hard fought environment as Formula One, I have always maintained that if you have a moment's doubt about what you are doing then it is time to stop. Privately I began to have these earlier this year and so have decided that now is the time to make my announcement.

"I'd like to thank to team for accepting my decision and I wish them all the best for the last race of the year."

Team boss Frank Williams said on Friday before the Chinese Grand Prix that Wurz may not retain his drive next year.

"Alex has been very reliable but I am not sure whether he is going to race again next year," Williams had told a news conference in Shanghai.

Wurz was running well in the wet but struggled towards the end of the race as the track dried out.

Wurz was a test driver with the team before being promoted to the race drive this year after Australian Mark Webber's departure for Red Bull. The Austrian scored 13 points to team mate Nico Rosberg's 15.

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