By Matt Majendie
BBC Sport in Liege
Lance Armstrong has said he is determined to fight doping allegations which have been made against him.
Armstrong will fight accusations
The five-times Tour de France winner has been accused in a new book of using performance-enhancing drugs.
But he said: "I will spend whatever it takes and however long it takes to bring justice to this case.
"In my view, extraordinary accusations must be followed up by extraordinary proof. The case will be a long one and I have already engaged lawyers."
He added: "The book's authors have worked for four or five years and have not come up with the proof."
This year's Tour starts in Liege on Saturday.