Jones facing two-year ban

American sprinter Marion Jones could face a two-year ban from athletics if a B sample confirms her initial failed drugs test.

Jones was a surprise withdrawal from Friday night's Weltklasse meeting in Zurich. Reports in the United States claim the 30-year-old has tested positive for EPO (erythropoietin), a blood-boosting hormone. Jones has already stated her innocence through her lawyer.

However Pierre Weiss, general secretary of the International Association of Athletics Federations, confirmed the world governing body were awaiting results of a B test.

Weiss told the BBC: "For us, the situation is clear, an athlete is only positive once an A sample has tested positive and the contra-analysis of the B sample confirms this. This is not the situation at the moment.

"We are waiting reports regarding this case, which is why we cannot speak more. We have spoken with USTAF (United States Track and Field) but we are still waiting for what the contra-analysis tells us about this case."

Jones has been dogged by allegations of drug taking since winning five Olympic medals at the 2000 Sydney Olympics, particularly during the the Bay Area Laboratory Co-operative (BALCO) drugs scandal.

However she has never faced charges and has repeatedly stressed she is a clean athlete.

Jones withdrew from Friday's Golden League meeting, citing "personal reasons" for having to return home.

Although that explanation would usually suffice in the case of an athlete withdrawing from competition, Weiss believes Jones could have been more open.

"We would have preferred that she stated what those personal reasons are. It would have made things more clear for the news media, the general public and the IAAF," he said.