His administration just released a major report detailing far-reaching impacts of the climate crisis. His response? “I don’t believe it.”

President Donald Trump was panned on Monday for his dismissal of his own administration’s recently released climate assessment.

“In all seriousness, the willful denial and obfuscation by Trump on climate change is a crime against humanity. Billions of people will bear incalculable harm for generations to come.  Much, much, much worse than possibly colluding to steal an election.” —Eric Holthaus

Speaking to reporters outside the White House, Trump said of the National Climate Assessment (NCA4), “I’ve seen it, I’ve read some of it, and it’s fine.” Asked about the report’s conclusions on the climate crisis’s economic impact on the country, Trump declared, “I don’t believe it.”

“We cannot afford a leader who sticks his head in the sand while people suffer the consequences,” said Michael Brune, executive director of the Sierra Club.

“The climate assessment, put forth by Donald Trump’s own administration,” Brune added, “makes it clearer than ever that if we don’t act now, the catastrophic effects of climate change will reshape the United States and the world to the detriment of those alive today, and for generations to come.”

Sen. Bernie Sanders (I-Vt.), for his part, said on Twitter the comment made the president “an international embarrassment and incredibly dangerous”:

Meteorologist Eric Holthaus weighed in on social media as well, calling “the willful denial and obfuscation by Trump on climate change… a crime against humanity”:

Another lawmaker commenting on Trump’s denial was Rep. Pramila Jayapal:

Some observers had already expressed outrage even before the 1,500-page report was released, saying the timing of the release—the Friday following Thanksgiving—was a ploy by the adminstration to limit news covereage of it.

Following its release, Brenda Ekwurzel, the director of climate science at the Union of Concerned Scientists and one of the NCA4 report authors, said, “In light of the report’s findings, it’s critical that federal, state, and local governments take aggressive action to protect U.S. residents by both reining in emissions and helping communities adapt to the climate impacts that are now inevitable.”

“While the report doesn’t offer policy recommendations,” she continued, “the findings certainly make a convincing case that the White House should stop rolling back climate policies and recognize that a much larger scale response is required to keep people safe.”