IAAF to appeal

The athletes were cleared by their national federation on March 18 in a shock decision after the Greek authorities said the pair were victims of incorrect procedures in notifying them of doping tests, including one just before the Athens Olympics.

However, both athletes are now suspended again pending the result of the appeal by the International Association of Athletics Federations' (IAAF) against the national federation's decision to clear the athletes of anti-doping rule violations.

"The Doping Review Board has concluded that the decision is erroneous and the IAAF will now refer both athletes' cases to arbitration before the Court of Arbitration for Sport (CAS) on a timely basis under IAAF Rules," the IAAF said on its website.

"The CAS decision in both cases will be final and binding." Kenteris, 31, who won a 200 metres gold medal at the 2000 Sydney Games, and Thanou, 30, a 100 metres silver medallist at the same Olympics, face two-year bans if they are found guilty.

The sprinters have consistently denied they were at fault and responsible for the Olympic movement's biggest athletics scandal since 100 metres gold medallist Ben Johnson tested positive for drugs at the 1988 Seoul Olympics.