World Anti-Doping Agency (Wada) chief Dick Pound has rejected the independent investigation which cleared Lance Armstrong of doping allegations.
Pound rejected the report's findings
Pound said Wada is considering legal action over the verdict into L'Equipe's claims that Armstrong's samples on the 1999 Tour de France tested positive.
He said the investigation headed by lawyer Emile Vrijman and the Dutch law firm Scholten "bordered on farcical."
Their report exonerated Armstrong and blamed anti-doping authorities.
It accused the Wada agency of behaving in ways "completely inconsistent" with testing rules, and determined the testing
procedures at the French national doping laboratory LNDD had
been insufficient to label the American's sample positive.
Vrijman also stated that Wada and the LNDD had effectively pronounced Armstrong guilty of a doping violation without sufficient basis.
The Vrijman report is so lacking in professionalism and objectivity that it borders on farcical
In a harshly worded statement, Wada said it completely rejected the report, its preliminary conclusion that "the report was defamatory to the Agency, its officers and employees, as well as the accredited laboratory involved."
The body has taken legal advice about its options against the investigator and any organisation, including the International Cycling Union (UCI), that may publicly adopt its conclusions.
"Wada is an independent agency, comprised of equal representatives from the sports movement and the governments, which is concerned with the integrity of sport and the health of the athletes who practise it," said Pound.
"Our only interest in this matter is to determine the facts in an objective manner, whatever they may be.
"The Vrijman report is so lacking in professionalism and objectivity that it borders on farcical.
"Were the matter not so serious and the allegations it contains so irresponsible, we would be inclined to give it the complete lack of attention it deserves."
The UCI and Wada have waged a long-running feud over several
doping issues, which is likely to continue after Wada's statement.
It also expressed "astonishment that the UCI would expect anyone to have the slightest confidence in the objectivity, methodology, analysis or conclusions of such a report, especially since UCI had had more than six weeks during which to review the draft report and to correct the many factual errors contained in it."
The UCI was unavailable for immediate comment.