NEW YORK, Dec. 28 (Xinhua) -- US cyclist Tom Zirbel announced in a statement that he tested positive in an "A" sample after the US Pro Time Trial Championships in August.

    Zirbel unveiled the announcement on cyclingnews.com saying he was still awaiting the results of the "B" sample test.

    Zirbel had been notified by the US Anti-Doping Agency of the positive result for an endogenous steroid Dehydroepiandrosterone (DHEA) in sample "A".

    "I want to inform the cycling community that an 'A' sample of mine from a urine test conducted by USADA on August 29, 2009 after the US Pro TT has tested positive for exogenous DHEA," Zirbel saidin the statement.

    "I have not yet received notification from USADA on the findings of the 'B' sample, but I expect to receive word any day now."

    Zirbel, 30, was contracted with the US-based Bissell Pro Cycling team from 2007-09. The noted time-trailer denied doping.