The 39-year-old from Michigan admitted that he had doped himself, by using erythropoietin (EPO) in preparation for the 1999 Tour de France, the year of Armstrong’s first victory. A second rider on Armstrong and Andreu’s US Postal Service Team also admitted, albeit anonymously, using EPO in training for that Tour.

Now Andreu, who said he made the admission because he was “bringing up the past to be able to clean up the present”, is facing up to the consequences of his actions. He has been vilified by some within his sport, but he maintained that the “positive responses were overwhelming”. Yet he has been dismissed from his role as team manager of the Toyota-United Cycling Team and has lost work as a commentator on American television coverage of next year’s Tour.

Andreu is unrepentant. “People are sick of the deceit, so I think it was a refreshing change for the truth to come out,” he said.

In 1999, as leader of the US Postal Service Team, Armstrong stunned the world of cycling with his Tour win, three years after he had had testicular cancer diagnosed. It was a watershed moment for American cycling. As a professional athlete, it was also a key moment for Andreu, who estimated that EPO had improved his own performance by a remarkable “20 per cent”. Andreu maintained that he did not take “anything else, ever” and that he doped only during training, before the 1999 Tour.

He is the fifth former team-mate of Armstrong to have tested positive or to have confessed to doping.

“I knew what I had done was wrong, but I had been getting my butt kicked for ten years,” he said. “Then I cracked and got tired of putting up with that. So I did it, but I didn’t feel totally guilty about it because everybody else seemed to be doing it. It was on my conscience, but I was only trying to keep up.”

Andreu denied that there was a structured culture of doping within his US Postal Service team. “Anybody who did anything did it individually, so there was no way of knowing if anybody else was doing anything,” he said. “I’m speaking about personal choices that I made. I was not put under pressure or told to do it.”

Andreu said that his confession was spurred by the spate of recent scandals and by “what was going on in the sport”. “There’s been no closure to a lot of these cases,” he said. “So I’m trying to change that. I realised that I had done something wrong and that I couldn’t speak freely until I admitted that I got caught up in it also. I was asked point blank if I did it and I thought, ‘Now’s the time to stop covering up things, to stop lying and to tell the truth.’ So I answered the question truthfully.”

Andreu’s initial admission came in The New York Times in September. But with the battle lines in cycling’s war on doping clearly drawn, his confession, and the implications of it, were not welcomed with open arms.

Johan Bruyneel, team manager to Armstrong during his seven Tour de France wins, described Andreu as a “pitiful man”. “I was disappointed that he made that remark instead of looking at the positive side of trying to clean up the sport,” Andreu said. “Obviously, he only thinks about himself and his team.”

Armstrong, who has consistently denied any involvement with performance-enhancing drugs, said: “This is a story about Frankie Andreu. The fact that he took drugs has nothing to do with me.”

• Tyler Hamilton, a former team-mate to Andreu and Armstrong in the US Postal Service Team, has signed a contract with Tinkoff, the Russian team. Hamilton, 35, the Olympic time-trial champion, will return to racing next season, after a two-year ban for blood doping.

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