Tour de France organisers have urged cycling's world governing body to make doping bans tougher in the wake of the Cofidis scandal.
"I'm publicly and officially asking the UCI (International Cycling Union) to agree to a two-year ban," said Tour organiser Patrice Clerc.
"I'm sure that the majority of the riders are not cheating but we have to get rid of those who are."
French police raided Cofidis premises on 12 January during a doping inquiry.
Clerc, president of Amaury Sport Organisation, the Tour owner, told French newspaper L'Equipe: "We must put our trust in the code of the World Anti-Doping agency (WADA).
"We must stop arguing that a two-year ban would be too harsh
"It will be an inch-by-inch, long-term fight.
"We all have to unite, riders, sponsors, federations, political
authorities, justice, police."
Two Cofidis team assistants and two riders, Cedric Vasseur
and Philippe Gaumont, were detained for questioning about the
alleged trafficking of banned substances.
Gaumont was released but is under official investigation, while Vasseur, who led the 1997 Tour de France for five days, was freed without charge.
The Cofidis affair threatens to be the biggest scandal in cycling since a large assortment of drugs were found in a Festina team car during the 1998 Tour de France.