Lance Armstrong, America's most famous cyclist, is facing formal doping charges from the U.S. Anti-Doping Agency that could cost him his seven Tour de France titles, it emerged late Wednesday.

In a 15-page notice letter obtained by The Wall Street Journal, USADA, the agency that oversees antidoping efforts in Olympic sports in the U.S., said numerous riders, team personnel and others will testify based on personal knowledge of Armstrong's alleged doping. The knowledge was acquired either through observing Mr. Armstrong dope or through admissions of doping to them, it added.

The letter also mentions data from blood collections obtained by the International Cycling Union, or UCI, in 2009 and 2010. This data is fully consistent with blood manipulation including use of use erythropoietin, or EPO, a drug that controls red-blood-cell production, and/or blood transfusions.

The letter also said Armstrong and five others -- including three doctors and a trainer -- had been involved in a team-wide doping program from 1998 to 2011 and that the USADA had witnesses to the conduct, ABC News reported.

USADA sources told ABC the charges would come by the start of the Tour de France, which occurs in July, to beat an eight-year statute of limitations.

With the official charges, Armstrong has been banned from competition in triathlons, a sport he took up after retiring from cycling in 2011, the Journal reports. He cannot compete in triathlons until the charges are resolved.

Armstrong issued a statement: I have been notified that USADA, an organization largely funded by taxpayer dollars but governed only by self-written rules, intends to again dredge up discredited allegations dating back more than 16 years to prevent me from competing as a triathlete and try and strip me of the seven Tour de France victories I earned.

He said the charges are baseless, motivated by spite and advanced through testimony bought and paid for by promises of anonymity and immunity. 

This is the product of malice and an unhealthy obsession with Lance, said his lawyer Bob Luskin. The more tests that he passes the more they seem to believe he is guilty. They've made a wicked bargain with other riders, telling them that they will not be charged if they implicate Lance and they will be banned if they don't. Nothing good or honest or fair or truthful can come out of this process. Lance hasn't ever doped and his innocence was supported by more than 600 successful drug tests.

The charges are new in the sense they have just been filed, but they are the same old charges from the same old people, Luskin said.

The USADA charges aren't criminal, but the agency has the power to ban athletes from competition and to revoke previous titles.

The case now is forwarded to a USADA review board, which examines written material only and recommends whether to proceed to an arbitration hearing. Armstrong has until June 22 to supply written materials to the review board.

The letter to Armstrong says that if a hearing is held, it should take place by Nov. 1 but could occur sooner, a person familiar with the case told USA Today on condition of anonymity.

An arbitration panel independent of USADA - probably a three-person panel made up of AAA, CAS and North American Court of Arbitration for Sport arbitrators - will rule on whether violations took place and, if so, what the punishment will be.

Travis Tygart, CEO of USADA, said in a statement that he will not comment on the evidence.

David Howman, director general of the World Anti-Doping Agency, which oversees USADA, declined to assess the strength of the evidence but told USA Today Sports, I think it's significant that it's not an athlete alone being charged. It's an athlete/entourage. I think the charge is significant.

Armstrong has never tested positive for performance-enhancing drugs.