Lance Armstrong said on Wednesday he will not cooperate with a US Anti-Doping Agency investigation into dope cheats in cycling but would be willing to help other anti-doping inquiries.

The move greatly diminishes Armstrong's chances of having his life ban from WADA-sanctioned sport reduced even as it forces USADA to move ahead without his help in looking into others involved in doping.

"For several reasons, Lance will not participate in USADA's efforts to selectively conduct American prosecutions that only demonize selected individuals while failing to address the 95 percent of the sport over which USADA has no jurisdiction," Armstrong said in a statement released through attorney Tim Herman.