(NEW YORK) -- Oprah Winfrey said on Tuesday that Lance Armstrong came well prepared for their highly anticipated interview, although he "did not come clean in the manner [she] expected."
Winfrey, who discussed the interview on CBS This Morning Tuesday, said, "We were mesmerized and riveted by some of his answers. I feel that he answered the questions in a way that he was ready. … He certainly had prepared himself for this moment. … He brought it. He really did."
Armstrong had apologized to staffers at the Livestrong Foundation before the Monday interview with Winfrey, and reportedly admitted to them that he used performance-enhancing drugs throughout his storied career.
Armstrong also confessed to Winfrey to using the drugs, sources have told ABC News. Winfrey said Tuesday morning that the entire interview, for which she had prepared 112 questions, was difficult.
"I would say there were a couple of times where he was emotional," she said. "But that doesn't describe the intensity at times."
As for the cyclist's sense of remorse, Winfrey said that will be for viewers to decide.
"I would rather people make their own decisions about whether he was contrite or not," she said.
The interview will air on the OWN network for two nights, starting at 9 p.m. ET Thursday and continuing on Friday.
Meanwhile, the federal government is likely to join a whistle-blower lawsuit against Armstrong, originally filed by his former cycling teammate Floyd Landis, sources told ABC News.
The government is seeking to recoup millions of dollars from Armstrong after years of his denying that he used performance-enhancing drugs, the sources said. The U.S. Postal Service, which is an independent agency of the federal government, was a longtime sponsor of Armstrong's racing career.
Sources tell ABC News the deadline for the government potentially joining in the matter was a likely motivation for Armstrong's interview with Winfrey.
The lawsuit remains sealed in federal court.
Armstrong is now talking with authorities about possibly paying back some of the Postal Service sponsorship money, a government source told ABC News on Monday.
The deadline for the department to join the case is Thursday, the same day Armstrong's much-anticipated interview with Winfrey is set to air.
Armstrong is also talking to authorities about confessing and naming names, giving up others involved in illegal doping. This could result in a reduction of his lifetime ban, according to the source, if Armstrong provides substantial and meaningful information.
The interview at his home in Austin, Texas, was Armstrong's first since officials stripped him of his world cycling titles in response to doping allegations.
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