Michael Moore sounded a dire warning on his social media accounts Tuesday, exclaiming that March 28, 2017 would be remembered as the day President Donald Trump caused the beginning of the planet-wide extinction of humanity.

In a post to his Facebook page, the 62-year-old documentary filmmaker and liberal activist accused Trump of declaring “war on the planet” after the president signed an executive order Tuesday rolling back several key Obama-era regulations concerning energy production.

“Historians in the near future (because that may be the only future we have) will mark today, March 28, 2017, as the day the extinction of human life on earth began,” Moore wrote on his Facebook page.

“This is a defining moment in the history of mankind. By signing these executive orders today, Trump is declaring an act of war on the planet and its inhabitants,” he continued. “The one silver lining here is that Trump can’t kill the planet; the planet wants to live and has a long history of wiping out any real or perceived threats.”

The filmmaker also warned that the planet was “paying attention” — and would itself dispose of a species “hell-bent on destroying Earth.”

In a statement Tuesday after signing the executive order, Trump said his administration was “putting an end to the war on coal.” The president was joined at the signing by EPA administrator Scott Pruitt, Energy Secretary Rick Perry, Interior Secretary Ryan Zinke and Vice President Mike Pence.

“We’re going to have safety, we’re going to have clean water, we’re going to have clean air, but so many are unnecessary and so many are job killing, we’re getting rid of the bad ones,” Trump said.

Moore — who released a surprise anti-Trump documentary shortly before the 2016 election — has become one of the president’s most outspoken celebrity critics. The director has used his social media accounts nearly daily to criticize Trump and comment on political news. In January, Moore vowed to lead “100 days of resistance” against the Trump administration.

Over the weekend, Moore blasted the ultimately unsuccessful GOP bill to repeal the Affordable Care Act, calling the effort “anti-woman” and “hateful.”

Last week, he urged Democratic Party to declare a “national emergency” until the FBI could investigate alleged connections between Trump campaign staffers and the Russian government.

Follow Daniel Nussbaum on Twitter: @dznussbaum