Former CIA Director John BrennanJohn Owen BrennanBrennan shreds 'misleading & highly politicized' Barr memo Attorney General Barr puts former intel bosses on notice Iranian president: 'Situation is not suitable for talks' with US MORE on Friday went after President TrumpDonald John TrumpA better VA, with mental health services, is essential for America's veterans Pelosi, Nadler tangle on impeachment, contempt vote Trump arrives in Japan to kick off 4-day state visit MORE over his attacks on former FBI Director James ComeyJames Brien ComeyFive takeaways from Barr's new powers in 'spying' probe Trump orders intel agencies to cooperate with Barr probe into 'spying' on 2016 campaign Attorney General Barr puts former intel bosses on notice MORE, tweeting that Trump’s “kakistocracy is collapsing after its lamentable journey.”

“As the greatest Nation history has known, we have the opportunity to emerge from this nightmare stronger & more committed to ensuring a better life for all Americans, including those you have so tragically deceived,” Brennan tweeted at Trump.

A kakistocracy is a form of government in which the worst persons are in power.

Brennan has been a regular critic of Trump, warning last month that lawmakers who protect him will face "a reckoning."

If anything, his criticisms have become more pronounced in the last few months. 

Trump lashed out at Comey in a pair of tweets early Friday, calling him a “leaker & liar” and an “untruthful slime ball.” 

ADVERTISEMENT

The attack came after multiple media outlets reported on excerpts of Comey’s upcoming book.

Comey writes in the book that Trump had asked him to probe the infamous “pee tape” mentioned in the so-called Steele dossier in order to disprove its existence. The dossier alleges that Trump hired prostitutes to urinate on a bed used by former President Obama and first lady Michelle ObamaMichelle LeVaughn Robinson ObamaTrump to meet with Prince Harry during UK visit Michelle Obama to headline Essence Festival Obama shares tribute to Michelle to celebrate Mother's Day MORE at the Moscow Ritz-Carlton.

Comey also ripped Trump as "untethered to truth" in the book and compared him to a mob boss.

“A Higher Loyalty: Truth, Lies, and Leadership” comes out Tuesday.