American Lance Armstrong has hired a criminal defence lawyer to represent him against a federal probe looking into allegations of possible doping violations in his cycling career.

The New York Daily News reported late Wednesday that the seven-time Tour de France winner Armstrong has hired Los Angeles-based lawyer Bryan D. Daly, a former federal prosecutor and partner at the firm Sheppard Mullin Richter and Hampton. Daly's hiring was first reported in a legal trade publication.

"I was recently retained by Mr. Armstrong to assist him with respect to the investigation by the US Attorney's Office in Los Angeles," the Daily News quoted Daly as saying.

"I have no comment at this time, except to say that we are going to work diligently to find out precisely what, if anything, this investigation has to do with Mr. Armstrong."

The federal investigation was sparked by accusations from Armstrong's former USA cycling teammate Floyd Landis in a series of e-mails sent to cycling and doping officials this spring. Armstrong has vehemently denied the doping allegations.