Fired FBI Director James Comey lashed out at President Donald Trump in a Monday opinion-editorial, referring to him as a “shrunken, withered figure.”

Writing in the Washington Post, Comey outlined what he described as the “four stages” of being criticized by the president and called on Americans to vote him out of office in 2020.

“What’s it like to be personally and publicly attacked by the president of the United States? Like many others in and out of government, I have some experience,” Comey wrote, adding:

It’s hard on good people, especially those who don’t have savings to fall back on. But the truth is that, in many ways, it is not as hard as you might think, especially as it continues endlessly, leaking power, shrinking its source.

Comey then went on to criticize President Trump’s foreign policy, singling out his decision to withdraw U.S. troops from northern Syria.

“I don’t mean to suggest Trump is not dangerous. The horrific betrayal of allies in northern Syria demonstrates that an impetuous and amoral leader can do great harm, even in shrunken form,” Comey wrote. He went on:

For the fourth, and final, stage, we need to fight through our fatigue and contempt for this shrunken, withered figure. Spurred by the danger he poses to our nation and its values, we have to overcome the shock and numbness of earlier stages. We must not look away.

Comey’s comments come after the Department of Justice Inspector General report revealed 17 “significant errors or omissions” in the FISA application to surveil one-time Trump campaign adviser Carter Page while Comey was at the helm of the bureau.

Appearing on Fox News Sunday, Comey admitted there was “real sloppiness” in FBI’s handling of its investigation into the Trump campaign.

He told host Chris Wallace:

He’s right. I was wrong. I was overconfident as director in our procedures of the FBI and Justice have built over 20 years years. I thought they were robust enough. It’s incredibly hard to get a FISA. I was overconfident in those because he’s right, there was real sloppiness — 17 things that should have been in the application or at least discussed and characterized differently. It was not acceptable, so he’s right. I was wrong.

President Trump responded to Comey’s admission with a demand for an apology and hinted the former bureau chief could see prison time for his actions.

The president tweeted:

So now Comey’s admitting he was wrong. Wow, but he’s only doing so because he got caught red handed. He was actually caught a long time ago. So what are the consequences for his unlawful conduct. Could it be years in jail? Where are the apologies to me and others, Jim?

President Trump fired Comey in 2017 at the recommendation of then-Attorney General Jeff Sessions and then-Deputy Attorney General Rod Rosenstein.