Teen activist Greta Thunberg scolds world leaders on climate — 'our house is still on fire' — but President Trump isn't singing her tune

Greta Thunberg — the teen activist who went on an oft-mocked "How dare you?" tirade about climate change at the United Nations in September — wasn't tearful or noticeably angry during her message Tuesday at the World Economic Forum in Davos, Switzerland.

But her address was just as accusatory toward global and big business leaders.

"Our house is still on fire," she said. "Your inaction is fueling the flames by the hour. And we are telling you to act as if you loved your children above all else."

"The climate and environment is a hot topic right now, thanks to young people pushing," Thunberg told those at the annual gathering in a ski resort in the Swiss alps, Bloomberg News reported. "Pretty much nothing has been done, since the global emissions of CO2 have not reduced."

The outlet added that only a handful of executives from the oil, gas, and coal industries "chiefly responsible for warming the planet" were in attendance. But another world figure was there, and he made some headlines of his own.

'This is not a time for pessimism'

President Donald Trump spoke at the forum later on Tuesday and didn't appear to be on Thunberg's frequency as he focused instead on America's growing economy and record oil and gas production, Bloomberg News said.

"This is not a time for pessimism, this is a time for optimism," the president said as Thunberg watched from the audience, the outlet reported. "We must reject the perennial prophets of doom and their predictions of the apocalypse. They are the heirs of yesterday's foolish fortune tellers."

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The president and the activist's first and only meeting last year became instantly viral as Thunberg was filmed furiously staring at Trump. While they've never spoken face to face, they both seem to follow each other closely on Twitter.

“Greta must work on her anger management problem, then go to a good old fashioned movie with a friend! Chill Greta, Chill!", Trump tweeted in December shortly after the activist was named person of the year by Time magazine. Thunberg didn't directly answer, but changed her Twitter biography to “A teenager working on her anger management problem."

But Thunberg did say toward the end of 2019 that she wouldn't have bothered to speak with Trump if she had run into him at the United Nations climate summit in September.