London ? All 189 Tour de France riders signed the UCI’s anti-doping charter in time for today’s opening prologue stage.

The International Cycling Union requested that all cyclists sign a charter saying they are not involved in doping and promising to submit DNA samples to Spanish authorities for the Operation Puerto probe. Cyclists also had to agree to pay a year’s salary on top of a two-year ban if caught doping.

“Every rider has signed the pledge. I’m very happy with that,” UCI president Pat McQuaid said Friday. “It shows a commitment from the riders and the teams for a clean future. With each rider it’s a personal commitment. It gives a message to the world that cycling is not completely driven with drugs.”

Tour director Christian Prudhomme had said that anyone who refused to sign would not race.

The Tour begins Saturday with a 4.9-mile prologue in London and ends July 29 in Paris.

Italian rider Enrico Degano is scheduled to start first, with last year’s runner-up, Oscar Pereiro, going last.