Valverde won the first stage in the 2008 Tour de France
Alejandro Valverde has failed to clear his name after the Court of Arbitration for Sport (CAS) upheld a two-year suspension for a doping offence.
The National Olympic Committee of Italy (CONI) had banned the Spanish rider in May 2009 after his DNA sample matched blood found at a Madrid clinic.
Traces of Erythropoietin (EPO) were found in the blood bag taken from the clinic during a police investigation.
The suspension remains in place until May 2011, but only on Italian soil.
That could mean the 29-year-old, who had argued the ban should not stand because Italian authorities had used Spanish evidence, is free to compete at the Tour de France which runs 3-25 July, but the International Cycling Union (UCI) have vowed to extend the ban worldwide.
The 2009 Tour of Spain winner is set to face further scrutiny on Thursday at CAS when both the World Anti Doping Agency (WADA) and the UCI attempt to force further investigation into Valverde's case.
In a statement released by the UCI, the group stated: "We welcome the decision of the CAS, which confirms the conclusions the UCI reached after conducting a thorough review of the documents relating to the Puerto case and of Alejandro Valverde's involvement in it.
"Consequently, after careful study of the grounds of the CAS decision, the UCI expresses its determination to take the necessary measures to secure a suspension that is applicable internationally."
Valverde was one of around 50 cyclists implicated when authorities in Span raided a clinic in 2006 used by Eufemiano Fuentes, a Spanish doctor alleged to have links with doping offences.
The investigation, named Operation Puerto, found large quantities of anabolic steroids, laboratory equipment used for blood transfusions and more than 100 bags of frozen blood at clinics in Madrid and Zaragoza.
However, most of the charges against riders were dropped after a court ruled much of the evidence could not be used, leaving Valverde free to compete.
Earlier this month the Spanish rider finished second in the Paris - Nice race behind compatriot Alberto Contador.