Kevin Downing, a lawyer for Mr. Manafort, did not respond to a message seeking comment.

In July, federal agents carried out an early-morning raid of Mr. Manafort’s home, taking binders stuffed with documents and copying Mr. Manafort’s computer files, looking for evidence that he set up secret offshore bank accounts.

Mr. Stone said on Tuesday that although he was not familiar with the details of Mr. Manafort’s finances, he believed that federal prosecutors were trying to pressure the former campaign chairman into testifying that members of the Trump campaign colluded with Russians to disrupt the election.

“I think what’s happening here is that the special counsel will try to manufacture a crime and then say, ‘Look, Manafort, we won’t prosecute you for this if you simply admit you were colluding with the Russians and Donald Trump knew everything,’” Mr. Stone said. “In other words, bear false witness against the president. I’ve known Paul Manafort for over 40 years, and I don’t believe he is going to do that. He is not going to lie, and that would be a lie.”

Mr. Stone also said he told the Intelligence Committee that he never worked with Russians to aid Mr. Trump’s campaign, and that he was unaware of any evidence that showed Russian “collusion with any member of the Trump campaign, Trump family, Donald Trump, Trump associates, Trump friends, Trump supporters.”

He said he did admit to the committee that he once exchanged messages with someone claiming to be Guccifer 2.0, an online persona that American officials believe was a front in the Russian hacking efforts and responsible for copying thousands of emails from the Democratic National Committee.