Quote:“Donald Trump’s press conference performance in Helsinki rises to & exceeds the threshold of 'high crimes & misdemeanors.' It was nothing short of treasonous,” Brennan tweeted.

But on Friday, Brennan gave a peculiar denial that was hard for MSNBC's Rachel Maddow to accept.

While he appeared on Maddow's show, he defended his comments, but clarified that he never meant to say that Trump committed treason.

“I didn't mean that he committed treason,” he told Maddow. After pressing him, Maddow said, “If we diagram the sentence, 'nothing short of treasonous,' means it's treason.”

Maddow said that, given Brennan's knowledge of Russian activity during the election, his treason comment suggested that the president was serving a foreign country over the United States.

“Well, yeah,” Brennan responded. “I think he has crossed the line repeatedly in terms of his failure to fulfill the responsibility of the office and to look Vladimir Putin square in the eye and say, 'this should never happen again.'”

When Maddow asked Brennan specifically whether he thought Trump was knowingly serving the Kremlin's interests, Brennan said he didn't know.