Disgraced US cycling star Lance Armstrong said in an interview broadcast on Thursday that he was "sorry" for taking performance-enhancing drugs during his career and that it was a mistake.

"I made my decisions. They're my mistake. And I'm sitting here today to acknowledge that and to say I'm sorry for that," the seven-time Tour de France winner said in an interview with Oprah Winfrey. "The culture was what it was."

"I view this situation as one big lie that I repeated a lot of times," Armstrong said, admitting that he was a "flawed character."

"All the fault and all the blame here falls on me," he said.

Armstrong, after years of denials, acknowledged in the interview taped on Monday that he took several banned performance enhancing substances during his cycling career.

Armstrong said he had blood transfusions and taken EPO, testosterone, cortisone and human growth hormone in all seven of his Tour de France victories.