Kazakh rider Alexander Vinokourov, who tested positive for blood doping during this year's Tour de France, announced his retirement from cycling.
"I've decided to end my professional career in cycling," the 34-year-old told Reuters in a telephone interview from his home in Almaty.
"I no longer have the motivation for competing but I have one more thing to do before I leave the sport for good, I want to clear my name."
Vinokourov was given a one-year ban by the Kazakh Cycling Federation on Thursday after testing positive for a homologous blood transfusion after winning a Tour time trial in Albi.
"I've been accused of something I've never done. I'm innocent and I want to prove it," he said.
"That's why I'm appealing the doping ban. On Monday I'm flying out to Europe where I will meet my lawyers to discuss this case.
"But I can tell you right now I'll be appealing it to CAS," he said, referring to the Lausanne-based Court of Arbitration for Sport.
Vinokourov, one of the pre-race favourites, was kicked out of the Tour following the positive result. His Astana team was also forced out of the race.
The Kazakh, who was subsequently fired by the Swiss-based team, blamed the French laboratory that analysed his samples for the positive test.
"The lab analysis were flawed, there was no accuracy in their tests," he said.
Vinokourov, who turned professional in 1998 with the Casino team and has 46 career victories including the 2006 Tour of Spain, said he had dreamt of a different ending.
"Since I started my professional career my aim was to go out on top as a champion, not like this, as a drugs cheat," he said.
"I wanted to end my career after winning this year's Tour," added Vinokourov, who finished third in the 2003 Tour and won the silver medal at the 2000 Sydney Olympics.
Vinokourov, who would be eligible to race again after his suspension ends in July 2008, ruled out a return.
"I'm not coming back even if I win the appeal. In my case a one-year ban instead of two years makes no difference," he said.
"It's like being sent to jail for a year while they investigate your case. It just doesn't work out for me, that's why I'm going to fight this injustice."