Frank Schleck's team Radio Shack Nissan Trek have withdrawn him from the Tour de France after he failed a dope test last Saturday.

The rider from Luxembourg tested positive for the banned diuretic Xipamide on July 14th, the Union Cycliste Internationale announced on Tuesday.

Schleck's Radio Shack team released a statement on Tuesday night, which read: "After being informed by the UCI about the presence of xipamide in the urine sample of Frank Schleck on July 14, the team has decided to immediately withdraw Frank Schleck from the Tour de France."

Schleck was 12th in this year's Tour de France, 9'45" seconds behind leader Bradley Wiggins. He finished third in the 2011 race.

The rider from Luxembourg is the older brother of 2010 winner Andy, who won the Tour de France after original winner Alberto Contador was stripped of his title for a doping offence.

A UCI statement, released before Radio Shack's response, read: "Earlier today, the UCI advised the Luxembourger rider Frank Schleck of an adverse analytical finding (presence of the diuretic Xipamide based on the report from the WADA accredited laboratory in Chatenay-Malabry) in the urine sample collected from him at an in competition test at the Tour de France on July 14, 2012.

"Mr Schleck has the right to request and attend the analysis of his B sample.

"The UCI anti-doping rules do not provide for a provisional suspension given the nature of the substance, which is a specified substance.

"However, the UCI is confident that his team will take the necessary steps to enable the Tour de France to continue in serenity and to ensure that their rider has the opportunity to properly prepare his defence in particular within the legal timeline, which allows four days for him to have his B sample analysed.

"Under the World Anti-Doping Code and the UCI Anti-Doping Rules, the UCI is unable to provide any additional information at this time."

The Radio Shack statement insisted that the reason for the positive sample was 'unclear' and that they would co-operate with the authorities on the matter: "Even though an abnormal A sample does not require these measures, Mr. Schleck and the team believe this is the right thing to do, to ensure the Tour de France can go on in calm and that Frank Schleck can prepare his defense in accordance with the legal timing to do so.

"On the subject of xipamide the team can declare the following: it is not a product that is present in any of the medicine that the team uses and the reason for the presence of xipamide in the urine sample of Mr. Schleck is unclear to the team. Therefore, the team is not able to explain the adverse findings at this point.

"However, the team is fully determined to collaborate with the anti-doping agencies in order to resolve the matter."

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