The IAAF expressed disappointment today with the Bulgarian Athletics Federation,s decision to clear star athletes Venelina Veneva and Vanya Stambolova on doping charges.

Both Veneva, the silver medallist at last year's European championships, and Stambolova, the European 400m champion, tested positive for "testosterone or its precursors" in an out-of-competition test conducted in Budapest on January 24. Veneva also provided a further positive sample from an out-of-competition test nine days later.

"The IAAF is disappointed in the decision taken by the Bulgarian Federation which we believe was not in accordance with IAAF Rules," the global governing body said in a statement on its website. "The IAAF will now immediately submit these two cases to the IAAF Doping Review Board who under IAAF Rules have the authority to refer both cases to the Court of Arbitration for Sport (CAS)." Veneva, 33, has been among the world,s premiere high jumpers for nearly a decade while Stambolova, 23, was among the event,s standout performers last year, a season in which she improved by more than three seconds, setting eight national records. The latter, 49.53 last August, was the third fastest performance in the world last season.

According to the IAAF, all three samples were analyzed at a World Anti-Doping Agency accredited laboratory in Lausanne, with all B samples confirming the initial A sample results.

Veneva was provisionally suspended by the Bulgarian federation on April 3, one month after winning the bronze medal at the European Indoor Championships in Birmingham. Stambolova's provisional suspension began on April 10.

Both Veneva and Stambolova were initially entered in last month's Golden League opener in Oslo, but later withdrew, citing injury.

The governing body,s review board is expected to meet on the case in the next few days. While the athletes are now free to compete, the suspension will be reimposed if the decision is made to appeal the cases to CAS.