The World Anti-Doping Agency director-general David Howman has criticised the decision of the judge in Spain's Operation Puerto trial to not release more than 200 blood bags for inspection.
Doctor Eufemiano Fuentes was given a one-year suspended sentence for endangering public health in the way he performed blood extractions and transfusions on a number of high-profile cyclists.
However, the judge in the case has refused to release the blood bags seized from Fuentes in 2006 and ordered them to be destroyed pending appeals from those parties involved.
Howman says the decision to order the destruction of all the blood bags is disappointing and unsatisfactory for WADA, and the whole anti-doping community which was hoping the bags could unmask other athletes involved in illegal doping.
The case is also expected to damage Madrid's bid to be the host city of the 2020 Olympics Games.
Spain's own national anti-doping agency has declared its intention to appeal the decision not to release the bags.