Transcript for Trump denies campaign communications with Russians

protests all over the country. Blockbuster allegations that trump insiders had contact with Russian intelligence officials during the presidential campaign and Brian Ross is here with a look at how rugs try to gain influence in the U.S. Reporter: Good morning, George. The trump white house continues to dispute reports that any of the president's associates were in contact with the Russians during the campaign. But there's no dispute the Russians themselves have been making great efforts to get close to trump and the people around him whether the targets knew it or not. It's every Russian spy's greatest dream, to have an asset, a source inside the white house or anyplace of power in Washington. They always target a political figure. They want to know who's a mover and shaker in our society, who affects it. Reporter: And as portrayed in "The Americans" for the Russians, all is fair in love and espionage. I'm in charge of FBI counterintelligence and my secretary married a kgb officer. Reporter: U.S. Intelligence officials describe a massive effort by Russian spies to infiltrate and disrupt American politics. Including the use of what are called cut-outs and front, people and organizations that would not appear to be part of Russian intelligence. This is a theory of war, a 21st century theory of war that includes false information that includes cyberhacking, that includes, you know, in effect sowing chaos. Reporter: Senator mark Warner is on a committee that is investigating into medding in the election and whether anyone in the trump campaign was involved. I think this investigation is maybe the most serious thing that I'll ever take on in my public career. Reporter: When general Michael Flynn was in Moscow in December 2015 invited to sit next to Russian president Vladimir Putin, he was about to become the senior foreign policy adviser for Donald Trump. Now the question for senate investigators and the FBI is why the Russians carted the general who was fired this week and trying to exploit him even if he did not realize it. If by his actions implied or implicit there was an effort to undermine American foreign policy, that bothers me a great deal. Reporter: Also under scrutiny another former trump foreign policy adviser, Carter page, who claims he's done major business deals with Russians and defends its leaders raising the eyebrows of American intelligence officials. Would you agree that Vladimir Putin is a thug as some have called him? You know, I thoroughly disagree. Reporter: Page is named as a central figure in the infamous dossier of unsubstance yachted claims about the Russians being in cahoots and told ABC news the allegations are ridiculous. Is it absolutely false? Completely false and laughable. And former trump campaign manager Paul manafort who once worked for pro-Russian politicians denies talking to anyone telling ABC news how am I supposed to know who is a Russian spy? The key word is knowingly. What else are they doing? There are questions about finances and Mr. Trump himself. There are doubts remain as long as he refused to release income tax returns, one of the big questions for investigators. Brian Ross, thanks very much.

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