Frenchman Virenque has been at the eye of the drugs storm in cycling this year after his Festina team was thrown out of this year's Tour de France in July.

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Masseur Willy Voet was found with drugs in a team car and manager Bruno Roussel subsequently admitted to organising doping.

But despite Voet's assertion that Virenque was guilty, the four-times King of the Mountains has persistently denied taking banned substances.

"All the biological parameters and tests prove scientifically that I'm not doped," he insisted last week after a judge ruled that he had tested positive.

'Work still undone'

The announcement of his retirement came in a statement released by his management group.

"Richard leaves with the impression that he had work still undone and asks that his supporters excuse him," it said.

"He would love to have continued and made dreams come true but he believes he is not being given the chance to do this."

Virenque wins a 1997 Tour stage in his favourite polka-dot jersey

"We had to take a decision that we didn't choose," said Lionel Virenque, the rider's brother and manager.

The 28-year-old had been linked with other teams, including Italian giants, Mapei, but Lionel Virenque said most were unwilling to take a risk.

"Big teams are worried", he said. "They are afraid of the press (being) against him."

Virenque's career will be remembered with mixed emotions.

The Moroccan-born rider was loved by the French public, where his good lucks and charisma ensured thousands lining the roads supporting him every July.

He rewarded them with four King of the Mountains awards, and came closest to the biggest prize with a second place in 1997.

But many cycling fans criticised him for his unwillingness to compete in races apart from the sport's annual highlight, and also for poor tactical decisions.

In that tour of 1997, he is widely regarded to have lost a chance to put pressure on the winner Jan Ullrich by waiting for fellow riders to help him during a mountain stage instead of attacking the young German.

Other mountain climbers such as this year's Tour winner Marco Pantani also criticised Virenque for taking the famous polka-dot jersey with points won on the easier mountains.

Unfortunately for Virenque, despite the debate over his riding style and achievements he is likely to be remembered as much for the Festina scandal as anything else.

Festina exodus

Most of his team-mates from this summer's Tour have already left Festina, which has had its budget cut in half.

Former Tour of Spain winner Alex Zulle moves to that country and Banesto, while fellow Swiss Laurent Dufaux is also continuing to ride.

But their debuts will be delayed until mid-season because of the bans imposed on them following their admissions of drug-taking.