COPENHAGEN - Denmark's top cyclist Michael Rasmussen Thursday admitted to extensive use of doping for 12 years, dealing a further blow to the sport since Lance Armstrong's confession.

Rasmussen said at a press conference in the city of Herning, western Denmark, that he doped continuously from 1998 to 2010 during his professional cycling career.

He was overall leader of the 2007 Tour de France until he was kicked off for not giving his whereabouts as he missed pre-race doping tests. Then he received a two-year ban.

According to Rasmussen, the prohibited substances he used include, among others, EPO, cortisone, hormones, and blood transfusions.

The 38-year-old will be provisionally banned as the Doping Commission of the National Olympic Committee is to open an investigation against him, and the case will be raised before an independent panel, the Doping Tribunal of the NOC, when all conditions are met.

Denmark's national anti-doping organization, Anti-Doping Denmark, reached out to the cyclist and got him to talk, with the cooperation from the NOC and Sports Confederation of Denmark, The Netherlands Doping Autoriteit, USAnti-doping Agency and World Anti-Doping Agency.

"I would like to thank our colleagues from the US and the Netherlands and WADA for excellent cooperation," said Lone Hansen, CEO of Anti-Doping Denmark. "The investigations of doping cases have improved very much recently, and this case is an excellent example of the implications of the work initiated by USADA's investigation."

"I am obviously disappointed to learn that Michael Rasmussen was doping throughout most of his professional career," said Hansen. "But on the other hand I would like to express my satisfaction over the fact that Rasmussen has decided to cooperate with the anti-doping authorities hereby providing us with valuable information, not only about other doping offences, but also giving us valuable insights into an otherwise secret part of professional cycling."