Marion Jones has returned all five Olympic medals she captured during the 2000 Games in Sydney, acccording to the American Anti-Doping Agency. Jones pleaded guilty last week for lying to federal agents in connection to using performance-enhancing drugs supplied by BALCO.

She confessed that she had taken tetrahydrogestrinone (THG) from September 2000 through to July 2001.

The 31-year-old won three golds in the 100 metres, the 200 metres and the 4x400m relay, and two bronzes in the long jump and the 4x100m relay at the Sydney Games.

"The outcome of this story is a valuable reminder that true athletic accomplishment is not obtained through cheating and any medal acquired through doping is only fool's gold," said Travis T Tygart, chief executive officer for the US Anti-Doping Agency.

Last Thursday, Jones admitted to friends and family in a letter to using steroids starting in 1999, a claim she had denied - even under oath during the BALCO investigations.

Jones has also accepted a two-year ban from the sport, while agreeing to forfeit all other results dating back to September 1, 2000 - including medals, points and prizes. However, she also announced her retirement last week when she admitted taking steroids to a New York court.

John Coates, president of the Australian Olympic Committee, welcomed Marion Jones's move to give back her Sydney 2000 medals, saying, "We certainly believe she should be stripped of the medals and feel sorry for the athletes who raced against her who were clean."

Coates, however, added that Ekaterina Thanou should not be awarded the 100 metres title despite. Thanou won 100m silver behind Jones but was later handed a two-year ban for missing doping tests during the 2004 Athens Games. The Greek sprinter denied taking performance-enhancing substances and returned to competition in 2006.

There is no suggestion she breached doping laws in 2000 but Coates still said: "I'd like to think that Katerina Thanou will not be awarded the gold medal, but there may be some legal difficulties for the IOC to overcome in order to reach that conclusion."

He added that the US athletes who won 4x400m gold and 4x100m bronze in Sydney would also have to return their medals.

"It is my expectation that the United States Olympic Committee will be required to also hand back the medals won by the other ladies who competed with Jones in the two relays," he said. "That is normal practice."