Former CIA Director John Brennan blasted President Trump with a scathing tweet following Monday's press conference with Vladimir Putin, decrying his comments as "imbecilic."

Trump and the Russian president stood together for a joint press conference after they met in a historic summit for about two hours in Helsinki, Finland.

Many were disappointed with Trump's comments that seemed to side with Putin over the U.S. intelligence community regarding Russia hacking the 2016 election.

Brennan said Trump's remarks that Putin "was extremely strong and powerful" in his denial of meddling were "nothing short of treasonous."

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Speaking with Harris Faulkner on "Outnumbered Overtime," Florida Rep. Ron DeSantis (R) responded to Brennan's message by saying that Brennan was "a disaster" as the head of the CIA.

"He was a member of the Communist Party during the Cold War," DeSantis said. "So this is not exactly the guy I would listen to about Russia."

Brennan admitted voting for Gus Hall, the Communist Party USA presidential candidate, in 1976.

A number of Republican lawmakers were also critical of Trump's press conference performance on Monday.

Sen. Lindsey Graham (S.C.) expressed his dismay at Trump's statement, calling it a "missed opportunity" by the president to hold Russia accountable.

The president shamefully placed blame on the United States, Arizona Sen. Jeff Flake said, adding that he never thought he would see such a day come.

DeSantis said that Trump missed an opportunity to say that the meddling occurred while Barack Obama was still in office.

"[Trump's] administration has been tougher on Russia than Obama," DeSantis said. "He's got a story to tell and I think that he should try to do that."

Watch the segment above.

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