"We are contesting the charges and will demand arbitration," said Don Goldberg, a spokesman for Montgomery's lawyer, Cristina Arguedas. A letter will be sent to USADA later on Monday, he said.

"Tim Montgomery has done nothing wrong, and we believe that any fair reading of the evidence in fact supports his innocence," Arguedas said in a statement June 18.

Under USADA protocol, persons charged with a doping offense may accept a ban or either seek a hearing before an American Arbitration Association panel comprised of North American members of the Court of Arbitration for Sport (CAS) or go directly to the Swiss-based CAS.

Montgomery and former world indoor 200 metres champion Michelle Collins were among four U.S. sprinters charged by USADA with doping violations that could bring lifetime bans from the sport. USADA is not a government agency.

Goldberg declined to comment Monday on a report that Montgomery told a federal grand jury in San Francisco that some elite runners were sickened by a drug -- code-named "clear" -- from BALCO, the San Francisco-area laboratory at the heart of the steroid scandal.

The San Francisco Chronicle said Montgomery told the grand jury investigating BALCO that he suffered negative side effects and got no benefit from the drug during an eight-month-period in 2000-2001.

Montgomery said the drug was a steroid that "was made for bodybuilders, not for sprinters" and did not improve his performance, the paper said, adding that it would not be detected in doping tests.

The paper did not say where it got the information.

On Friday, a U.S. judge ordered federal prosecutors to investigate the source of leaked grand jury testimony in the doping case and asked defendants and their lawyers to sign affidavits to not release transcripts.

Conte and three other men were indicted in February for operating a drug ring to illegally distribute growth hormone and steroids to athletes. They have pleaded innocent.