The announcement late Tuesday that Armstrong had granted the exclusive interview came as more allegations were to be made public about the cyclist who had held the record for the most Tour de France wins, The New York Times reported.
Winfrey said the "no holds barred" interview will be broadcast on her OWN cable network next week.
Armstrong has denied allegations of cheating, but has been reported as saying he was considering a public admission of doping as a way of restarting his career.
Travis Tygart, the head of the U.S. Anti-Doping Agency, which accused Armstrong of using performance-enhancing substances in a 202-page report issued in October, was expected to make new allegations against him during an interview Wednesday night on CBS.
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