Tour de France chief Christian Prudhomme said Saturday that organizers could have refused to allow Michael Rasmussen to compete in this year's race if they had known that he had missed several random doping tests in the past two years.

The Danish Rabobank rider is leading the world's most prestigious cycling race.

But it emerged this week that the Danish Cycling Union (DCU) decided in June not to select Rasmussen for September's world cycling championships and the Olympic Games in 2008 because he missed out-of-competition tests.

Rasmussen has had several warnings from the UCI and Danish anti-doping authorities for failing to communicate the locations of his training sessions.

"What I regret more than ever is that we didn't have this information on June 29, or on the following days before the Tour started," Prudhomme told AFP. "We would have made the Rabobank team face up to their responsbilities."

According to a source close to the dossier, the UCI knew about the case and had asked Rabobank to pull its rider before the Tour.

"If they really did, then it's good, but if they asked and they did not succeed, it's serious," said Prudhomme. "It's increasingly difficult for me to have confidence in the UCI leadership."

On Friday, Prudhomme accused the UCI of using the affair to try to weaken the Tour de France.