Paris: French Anti-Doping Agency (AFLD) president Pierre Bordry said on Friday he had resigned.
"I have resigned. The agency has reached a level of competence that has been acknowledged by the World Anti-Doping Agency (WADA)," Bordry told Reuters by telephone.
The precise reason for Bordry`s resignation was not immediately clear.
"Important decisions are to be made in the near future and since I had only a few months left in my presidency I wanted to pass it on now," he said, without elaborating.
Under Bordry, the AFLD had samples from the 2008 Tour de France cycling race re-tested for the banned blood-boosting substance erythropoietin (EPO), leading to several top riders being suspended.
Bordry was involved in several rows, most notably with the International Cycling Union (UCI), whom he accused of giving preferential treatment to Alberto Contador`s and Lance Armstrong`s then Astana team in the 2009 Tour de France.
UCI president Pat McQuaid told Reuters: "I hope for the sake of the fight against doping, which is so important for the integrity of sport, that UCI can find a good collaboration with his successor and AFLD."
Seven-times Tour champion Armstrong said on his Twitter feed: "Au revoir, Pierre."
Bordry`s successor is set to be named next Friday by the French presidency on the recommendation of the French Council of State.
Bordry, who started his job in July, 2005, complained last week that the AFLD lacked the funds to reach his target of 9,000 doping tests per year.