The French Anti-Doping Agency said on Monday that new tests will be used to catch a previously undetectable banned substance during this year's Tour de France, which starts in Monaco on July 4.

AFLD president Pierre Bordry announced it at a press conference. He declined to say which banned substance could now be tested for or give the method used to detect it, although he said it was not fully ready yet.

The International Cycling Union (UCI) has again allowed French anti-doping authorities to keep riders' samples taken during the three-week long race so they can be retroactively tested, Bordry added.

During last year's Tour, Italian climber Riccardo Ricco tested positive for CERA, a new generation of the banned blood-booster erythropoietin (EPO), while Austrian Bernhard Kohl got caught through retroactive tests after the Tour had ended.

(Xinhua News Agency June 24, 2009)