Tour de France officials and representatives from Astaná-Würth are both taking their cases to the Court of Arbitration in Sport following Monday’s request by Tour organizer ASO to kick the scandal-stained Astaná-Würth out of Saturday’s start of the 2006 Tour.

Tour officials sent faxes to Astaná-Würth as well as to the UCI and representatives of the professional teams association Monday after indicating the the Spanish team – formerly Liberty Seguros-Würth – was no longer welcome for the 93rd Tour, set to start Saturday with a prologue in Strasbourg.

The decision was precipitated by a string of damning stories printed in Sunday’s and Monday’s editions of El País, Spain´s leading national newspaper. The paper has had unprecedented access to secret court and police documents and said it has cracked many of the names on a coded list obtained by police in a series of raids in May.

Spanish courts still haven’t released any documents or have filed any indictments, but the unofficial leaks and reports working their way into the Spanish media are having a devastating effect.

Earlier this month, Comunidad Valenciana saw its Tour invitation revoked after Ignacio Labarta, one of the team’s assistant sports directors, was among five people detained as part of “Operación Puerto.”

El País reported that as many as 15 Astaná-Würth riders were on coded lists of racers allegedly treated by Spanish doctor Eufemiano Fuentes, also detained May 23 as part of the largest doping investigation in Spanish sports. Former team manager Manolo Sáiz was also detained by Spanish authorities.

El País also reported that seven of nine starting riders from last year’s Tour were on Fuentes’ alleged medical rolls.

Despite the unofficial nature of the reports, it was enough to prompt Tour officials to act. Stung by a string doping controversies dating back to the 1998 Festina Affaire, Tour officials are keen to pre-empt any hint of scandal ahead of cycling’s marquee race.

The decision, however, undercuts the integrity of cycling’s 20-team ProTour league, which guarantees start positions for all member squads in the Tour, the Giro d’Italia and the Vuelta a España as well as other major events.

Just last week, the UCI approved an extension of the ProTour license for the team following a change in title sponsor, Astaná. Cycling’s governing body said it made its decision based only on financial criteria, not on allegations making headlines across Europe.

Team officials confirmed Tuesday it is challenging the decision to CAS, an action that ASO is also ready to challenge to CAS if the team tries to show up Saturday in Strasbourg.