Floyd Landis, fighting a doping scandal that could cost him the Tour de France crown, made his case on US television on Friday and received a vote of confidence from seven-time Tour winner Lance Armstrong.

Landis, appearing on CNN's "Larry King Live" programme from Madrid, reiterated that his positive test for an abnormal testosterone-to-epitestosterone level "was a shock as much to me as anyone else."

He said he would do everything he could to clear his name.

"I'm going to do my best to defend my dignity and my innocence," said the American who rides for the Swiss-based Phonak team.(
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Armstrong, who has himself been dogged by doping allegations that he has consistently denied, spoke to the Los Angeles-based King on the broadcast by telephone.

"Obviously, I was very surprised," Armstrong said of Landis's positive result, which has yet to be confirmed by a B sample test. I was at the Tour. I watched Floyd ... I thought it was unlike anything I've seen in cycling - and I mean that in a good way."

But Armstrong acknowledged the affair was a blow to cycling.

"Although I still believe in Floyd and believe him to be innocent, it's not good for cycling," Armstrong said.

Armstrong said that there was never any suggestion during Landis's three years on Armstrong's US Postal team that the younger rider would be seduced by the lure of performance enhancing drugs.

"If we ever suspected anything to lead us to believe he was a cheater, we would have parted ways long before we did," Armstrong said. "When he did leave, he left for a better offer from another team."

Landis said that although he had clashed with Armstrong in the past, the two were "back to being friends again," noting that his current predicament had given him insight into what Armstrong has gone through at the hands of his accusers.

"I saw what he went through, and I didn't feel it because I hadn't gone through it myself, and now I can relate," Landis said.

Armstrong also noted that the French laboratory that conducted the test on Landis was the same one which was involved in some of the allegations against himself.

"I'm a little sceptical of this particular laboratory," the now retired Armstrong said.

But both Landis and Armstrong refused to be drawn on whether the suspicions they face owe anything to anti-Americanism.

"I don't know that that's the motive behind this," Armstrong said in response to a question from King.

"I have met plenty of wonderful people in every country I've gone to," Landis added, "so I'm cautious about saying things like that."