(CNN) -

The U.S. Anti-Doping Agency said Friday that it has filed doping charges against champion cyclist Lance Armstrong.

This month, the agency announced that it was opening proceedings against Armstrong and five former teammates.

"USADA can confirm that the independent three person Anti-Doping Review Board (ADRB) has conducted a full evaluation and has made a unanimous recommendation to move forward with the adjudication process in accordance with the rules," it said in a statement.

If Armstrong and the others choose, the case will move next to an arbitration panel, 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," the agency said.

Armstrong has always insisted that he never took performance-enhancing drugs. Other riders accused him of using such drugs, but he has never failed a drug test.

"There is not one shred of credible evidence to support USADA's charges," Armstrong's attorney, Robert Luskin, said in a statement. He described the agency's decision as "wrong" and "baseless."

"In its zeal to punish Lance, USADA has sacrificed the very principles of fair play that it was created to safeguard. It has compiled a disgraceful record of arrogance, secrecy, disregard for its own protocols, shabby science, and contempt for due process," Luskin said.

When the proceedings were announced this month, Armstrong said the Anti-Doping Agency intended to "dredge up discredited" allegations against him in a bid to strip him of his seven Tour de France victories.

"Unlike many of my accusers, 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," Armstrong wrote on his website. "That USADA ignores this fundamental distinction and charges me instead of the admitted dopers says far more about USADA, its lack of fairness and this vendetta than it does about my guilt or innocence."

According to its website, the quasi-government agency is recognized as the official anti-doping agency for Olympic, Pan American and Paralympic events in the United States.

The World Triathlon Corporation suspended Armstrong this month from competing in WTC-owned and -licensed races while he's under investigation for doping. USA Triathlon said he can still compete in its events.

In February, Justice Department prosecutors said they closed a criminal investigation after reviewing allegations against Armstrong. They had called witnesses to a federal grand jury in Los Angeles, but they apparently determined they lacked evidence to bring a charge that Armstrong used performance-enhancing drugs.

CNN's Scott Thompson and Dana Ford contributed to this report.