Transcript for Trump's long-time adviser says he never spoke to the president about Russia

And president trump's longtime adviser, Roger stone, attacking the FBI. Accusing them of gestapo tactics during his arrest. Two days after being indicted, stone now signaling a willingness to cooperate with Robert Mueller. Saying he never spoke to the president about wikileaks or Russia, or about Mueller's investigation. His critics say the evidence against him is right there. Here's Tara Palmeri. Reporter: Tonight, president trump's longtime political adviser, Roger stone, denying he ever communicated with trump about Russia or the Mueller investigation. None whatsoever. Zero. Categorically? Zero. Reporter: Robert Mueller indicted stone Friday in seven counts including obstruction of justice, witness tampering, and lying to congress. In court filings, Mueller paints stone as an intermediary between the campaign and wikileaks. Now out on bail, stone, defiant. Accusing Mueller of trying to intimidate him with the predawn FBI raid on Friday. They could have called my lawyers and I would have turned myself in. But it was an expensive show of force to try to depict me as public enemy number one. These are gestapo tactics. Reporter: Court documents allege he threatened witnesses. Calling one a rat, and sending an e-mail that said, let's get it on. Prepare to die. Stone offering this explanation. I do have a million e-mails, they have been reported, many of them taken out of context in this indictment. But there's nothing to find. Reporter: Mueller claims stone was directed by a high-level trump campaign official. A charge he denies. But stone does not rule out cooperating with the special counsel. If there's wrongdoing that I know about, I would testify honestly. I'd also testify honestly about any other matter, including any communications with the president. We spoke on the phone, but they're political in nature, and they're benign. Reporter: Adam Schiff says it's too early to rule that out. I would expect, if there's a collusion indictment, it would be the last indictment that Bob Mueller would seek. Not the first. We'll have to wait to see what evidence he produces. Tara, stone also defended himself about claims that he lied to congress about talking to a witness? Reporter: That's right, Tom. Stone claims he forgot that he contacted the witness, even though Robert Mueller has documents showing that the two text messaged more than 30 times on that day in question. Tara, thank you. And the 2020 race for

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