US Anti-Doping Agency chief executive Travis Tygart says the agency will ban Lance Armstrong from cycling for life and strip him of his seven Tour de France titles for doping.
Armstrong on Thursday night dropped any further challenges to USADA's allegations that he took performance-enhancing drugs to win cycling's premier event from 1999-2005.
"There comes a point in every man's life when he has to say, 'Enough is enough,'" Armstrong said in a statement posted on his website Lancearmstrong.com
"For me, that time is now. I have been dealing with claims that I cheated and had an unfair advantage in winning my seven Tours since 1999," he said.
Armstrong said USADA doesn't have the authority to vacate his Tour titles. However, Tygart told The Associated Press that the USADA can do it.
Tygart called the Armstrong case a "heartbreaking" example of a win-at-all costs approach to sports. In the statement, Armstrong did not concede having used performance enhancing substances during his celebrated cycling career.
On the contrary, he said he would "jump at the chance" to put the allegations to rest. But Armstrong said he refused to participate in the USADA process, which he called "one-sided and unfair".
The Austin American-Statesman reported that Armstrong also alerted the USADA in a letter sent just before a midnight
Thursday deadline that he would not fight the charges through arbitration. "Today I turn the page. I will no longer address this issue, regardless of the circumstances," he said in the statement.