The head of the World Anti-Doping Agency urged drug cheats Tuesday to withdraw from their Olympic teams and stay away from the London Games.

WADA President John Fahey said athletes will face the strictest ant-doping program in Olympic history and stand only a small chance of escaping detection.

"I say this in the clearest way possible: If you are a doping athlete and you are planning to compete in London then you must withdraw from your Olympic team," Fahey said in a statement, less than three weeks before the opening ceremony. "Even if a doping athlete were to win a medal, he or she would never be able to look at themselves in the mirror and say, 'Well done, I deserved this.'"

Fahey noted that anti-doping bodies around the world are seeking to catch cheats before the games, and the IOC and London organizers will be carrying out up to 6,250 tests during the games.

"These will be the most-tested games in Olympic history and doping athletes must know that they will be under the severe scrutiny of anti-doping officials from the moment they set foot in the Olympic Village," Fahey said.

Athletes suspected of doping are being targeted and will be tested at training camps before the games, which run from July 27 to Aug. 12.

"Doping athletes should know that their chances of avoiding detection are the smallest they have ever been," he said.

He added it's up to the athletes to keep the games clean.

"The world's anti-doping community can only do so much," he said. "If every athlete decides not to dope then we will have a completely dope-free games, that's the simple reality ... I urge them to collectively take more responsibility for the sake of clean competition."