WATCH: Brennan calls Trump “unfit for” office, claims he’ll use any tactic to stay in power

Appearing on MSNBC, former CIA director John Brennan called President Trump “unfit for this high-esteemed office.”

Brennan argues Trump should have acted upon the intel of Russia allegedly offering bounties for the deaths of U.S. soldiers.

Brennan has been an outspoken Trump critic since he took office.

His most recent tweet is:

.@realDonaldTrump is thoroughly, irredeemably, & dangerously broken.

Like other unprincipled despots, he will use any tactic to retain power.

This is our most serious domestic challenge in over 150 years.

Be on the right side of history. Ensure his landslide defeat & vote.

WATCH: