The U.S. Anti-Doping Agency's review board have unanimously recommended charging seven-times Tour de France winner Lance Armstrong with using performance-enhancing drugs during his record-breaking career, USADA said on Friday.
The latest step in the process that began earlier this month means the case will go to an arbitration hearing should the American elect to challenge the charges, which he has indicated he will.
"The three-person review board has conducted a full evaluation and has made a unanimous recommendation to move forward with the adjudication process in accordance with the rules," USADA said in a statement.
Armstrong's lawyer Robert Luskin said the agency was "obsessed" with prosecuting the former cyclist.
"USADA's decision to charge Lance Armstrong with doping violations is wrong and it is baseless," said Luskin in a statement.
"But it is utterly predictable given the CEO of USADA, Travis Tygart, has been obsessed for six years with pursuing Mr. Armstrong.
"(USADA) has compiled a disgraceful record of arrogance, secrecy, disregard for its own protocols, shabby science and contempt for due process. Mr. Armstrong is exploring all his legal options," Luskin added.
Five of Armstrong's associates, three doctors and two team officials, were also told earlier this month that procedures had begun against them in what could be one of the biggest doping cases in sport.
Armstrong, who has never failed a doping test, has denied the charges.
"I have never doped," he said in a statement when USADA first outlined their accusations of doping violations committed by him from 1998 to 2011.
"I have competed as an endurance athlete for 25 years with no spike in performance, passed more than 500 drug tests and never failed one."
Allegations included prolonged use of a range of performance-enhancing drugs including erythropoietin (EPO), blood transfusions, testosterone, corticosteroids, human growth hormone and masking agents.
The Texan was also accused of trafficking and administering drugs to other cyclists.
"All respondents will have the opportunity to exercise their right to a full public arbitration hearing, should they so choose, where all evidence would be presented, witness testimony would be given under oath and an independent group of arbitrators would ultimately decide the outcome of the case," USADA said.
Armstrong is one of the most successful and controversial cyclists of all time.
A cancer survivor, he returned to the sport after beating the illness and won the Tour de France an unprecedented seven times in succession from 1999 to 2005.
Although he never failed a doping test, Armstrong has been dogged by accusations of cheating.
The U.S. Justice Department spent two years investigating claims against him but closed their case in February without bringing any formal charges against him.
Armstrong said USADA's accusations were the same as those investigated by the Justice Department.
"These charges are baseless, motivated by spite and advanced through testimony bought and paid for by promises of anonymity and immunity," he said.
If found guilty the 40-year-old Texan, who has retired from cycling and taken up triathlon, could face a life ban from competition.