Washington, Jun 14 (IANS): Seven-time Tour de France champion Lance Armstrong is facing new charges from the US Anti-Doping Agency (USADA).

The American, who has switched to the triathlon after retiring from cycling last year, in a statement Wednesday, dismissed the latest allegations as "baseless" and "motivated by spite," Xinhua reported.

Armstrong, 40, last won the Tour de France title seven years ago.

Armstrong has been dogged by doping allegations since his first Tour victory in 1999. He managed to hold all his titles after US federal prosecutors closed a two-year criminal investigation in February without bringing any charges.

But USADA officials insisted they would continue to pursue their own probe into Armstrong and his former teams and doctors, and notified him of the charges in a 15-page letter Tuesday. Unlike federal prosecutors, USADA isn't burdened by proving a crime occurred, just that there was use of performance-enhancing drugs.

In its letter, USADA said its investigation included evidence dating back to 1996. It also included the new charge that Armstrong blood samples taken in 2009 and 2010 are "fully consistent with blood manipulation including EPO use and/or blood transfusions." Armstrong came out of his first retirement to race in the Tour de France those two years.