Updated

American basketball star Diana Taurasi has had her contract terminated by Turkish club Fenerbahce after her "B'' sample tested positive for doping.

The Istanbul club says the decision was made Thursday following the results announcement by the Turkish Basketball Federation. Taurasi faces a ban of up to two years, putting in jeopardy her chances of playing for the United States at the 2012 London Olympics.

Taurasi's "A'' sample tested positive last month for the banned stimulant modafinil following a Turkish league game on Nov. 13. Taurasi had been suspended by Fenerbahce ever since.

The Turkish federation, which announced the positive "B'' sample result on its website, says there has been no immediate decision on Taurasi's punishment.

THIS IS A BREAKING NEWS UPDATE. Check back soon for further information. AP's earlier story is below.

ANKARA, Turkey (AP) — Diana Taurasi's "B'' sample tested positive for doping, putting in jeopardy her chances of playing for the United States at the 2012 London Olympics.

Taurasi's "A'' sample tested positive last month for the banned stimulant modafinil following a Turkish league game on Nov. 13. The Fenerbahce player, who has been provisionally suspended by the team, could now be banned for two years.

The Turkish Basketball Federation, which announced the positive "B'' sample result Thursday on its website, said there was no immediate decision on Tauarsi's punishment. Fenerbahce said the club would make a final decision on her case at a later date.

If Taurasi is suspended for more than six months it could keep her from playing in the 2012 Olympics. She helped the team win gold medals at the past two Olympics and was the leading scorer at the women's world championships, which the Americans won in early October.

The International Olympic Committee bars any athlete given a doping penalty of six months or more from competing in the next games.

Modafinil is used to counter excessive sleepiness due to narcolepsy, shift-work sleep disorder or sleep apnea, according to drug manufacturers.

On Tuesday, Geno Auriemma, the U.S. coach for the 2012 Olympics, said the former University of Connecticut star told him that she did not take modafinil. He also said he didn't know if Taurasi had any problems with sleeplessness.

Taurasi led the WNBA in scoring for a league-record fourth straight year, averaging 22.6 points last season. The five-time All-Star and two-time WNBA champion signed a multiyear contract extension with Phoenix in August.

Taurasi is one of many American stars who play overseas in the winter because salaries are significantly higher than in the WNBA. She played in Russia for four years for Spartak before joining the Turkish league this season. Taurasi was leading the league in scoring with 24.6 points per game.

Two of Taurasi's teammates at Fenerbahce have resisted doping tests in Turkey because they do not trust the lab that tested her samples. Australian player Penny Taylor and Czech teammate Hana Horakova provided samples only after the Turkish federation agreed to send them to Germany for testing at a lab in Cologne.

The two players were tested after Fenerbahce's Turkish league game on Sunday.

Modafinil has been involved in several major doping cases, including that of American sprinter Kelli White, and is on the World Anti-Doping Agency's list of banned substances.

White won the 100- and 200-meter races at the 2003 world championships in Paris, but both of her medals were stripped after she tested positive for the stimulant.