(CNN) - It has been more than three months since president trump fired Acting Attorney General Sally Yates for refusing to enforce Trump's travel ban.
Yates testified before the Senate last week.
She said that before her firing, she warned the White House that Trump's then national security adviser had lied about his contacts with the Russians.
Michael Flynn was fired 18 days later.
When asked if she thought that Flynn's conduct was a fireable offense, she said, "I can't speak to a fireable offense. It's up to the president to make that decision about what he was going to do, but we certainly felt like they needed to act."
Cooper: (White House Counsel) Don McGahn asked you at that first meeting whether or not you thought the National Security Adviser should be fired. What did you say?
Yates: I told him it wasn't our call.
Cooper: Was the underlying conduct illegal? Was illegality involved?
Yates: There's certainly a criminal statute that was implicated by his conduct.
Cooper: You wanted the White House to act?
Yates: Absolutely, yes. We expected the White House to act.
Cooper: Did you expect them to act quickly?
Yates: Yes.
Cooper: There was urgency to the information?
Yates: Yes.
Cooper: On a personal level, I don't know if you can answer this or not. You're in government one week, you get fired, and now you're out and you're watching day after day after day go by and nothing seems to have happened to the National Security Adviser that you informed the White House about. Just as a private citizen at that point, did it concern you?
Yates: Well sure, I was concerned about it. But I didn't know if something else had been done that maybe I just wasn't aware of.
Cooper: Like maybe they were keeping him away from certain classified information while they were investigating. Something like that?
Yates: Maybe? I just didn't have any way of knowing what was going on at that point.
Cooper:: Were you aware that he sat in on, even from media reportsm that he sat in on a phone call with Russia's president?
Yates: Just from media reports.
Cooper: Did you find that surprising?
Yates: Well sure. Absolutely that was surprising.
Cooper: Sean Spicer said on the day after Michael Flynn resigned that it was a trust issue that led to his resignation, not a legal issue. Do you agree there was no legal issue with his Flynn's underlying behavior?
Yates: I don't know how the White House reached the conclusion that there was no legal issue. It certainly wasn't from my discussion with them.
Cooper: Do you think Michael Flynn should have been fired?
Yates: I think this was serious compromise situation, that the Russians had real leverage. He also had lied to the Vice President of the United States. Whether he is fired or not is a decision by the president of the United States to make but it doesn't seem like that's a person who should be sitting in the National Security Adviser position.
Cooper: Mike Flynn was let go after the Washington Post reported a story. Some Republicans have accused you of leaking it. Did you leak to the Washington Post?
Yates: Absolutely not.
Cooper: Did you authorize someone to leak to the Washington Post?
Yates: Absolutely not. I did not and I would not leak classified information.
Cooper: Have you ever leaked information?
Yates: No.
Cooper: The president seems to suggest that you were behind this Washington Post article. The morning before he testified he tweeted, "Ask Sally Yates under oath if she knows how classified information got into newspapers soon after she explained it to White House Counsel." It does sound like he ... he seems to believe you're the leak. Does that ... when you heard that, what'd you think?
Yates: There have been a number of tweets that have given me pause.
Cooper: You want to elaborate on that?
Yates: No.
The interview with Yates airs Tuesday night at 8 p.m. Eastern time.
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