Transcript for Former CIA director admits to concerns of Russia ties during Trump's campaign

Meantime the president and his team well aware of the headlines back home. Another major development today the former head of the CIA testifying on capitol hill, he said associates of the trump campaign were in touch with the Russians and often and that it worried him. Mary Bruce on the hill again tonight. Reporter: On capitol hill today, blunt talk from the former CIA director. I encountered and am aware of information and intelligence that revealed contacts and interactions between Russian officials and U.S. Persons involved in the trump campaign. Reporter: For the first time, John Brennan saying during the campaign he was concerned about ties between the Russians and the trump campaign. So much so, he thought the FBI should investigate and he warned the Russians to cut it out. It raised questions in my mind again whether or not the Russians were able to gain the cooperation of those individuals. Reporter: But today he stopped short of calling it collusion. I don't know whether or not such "Collusion" -- and that's your term -- such collusion existed. I don't know. Reporter: That question is now at the heart of multiple investigations. And now, "The Washington post" now reports president trump asked two of his top intelligence officials to publicly deny any coordination with the Russians. One of those officials, the director of national intelligence, pressed by lawmakers today, would neither confirm nor deny. It's not appropriate for me to comment publicly on any of that. Reporter: For now, the director isn't saying anymore. We've said all we're going to say. Mary Bruce joins us live tonight from capitol hill. Mary, you're getting word that the president is hiring a private attorney to deal with all this. David, we just lirnd that the president is expected to hire a private attorney to represent him in the special koucounsel's investigation. David.

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