Teenage activist Greta Thunberg blasted the US President about his "inaction" in tackling the climate crisis and said his lack of urgency is “fuelling the flames”.
Speaking to world leaders and global business players at the World Economic Forum (WEF), the 17-year-old said Donald Trump ’s plan to plant more trees was sorely inadequate.
She also called for an immediate end to fossil fuel investment in front of a packed audience.
“Unlike you, my generation will not give up without a fight. Our house is still on fire,” she told the room at the conference in Davos, Switzerland.
“Your inaction is fuelling the flames.”
Her comments come after Mr Trump attacked Ms Thunberg and other campaigners who have repeatedly asked world leaders to address the climate crisis.
Addressing such activists, Mr Trump earlier said the US would plant one trillion trees but also spoke at length about the economic importance of oil and gas.
“This is not a time for pessimism. This is a time for optimism,” he said during his keynote speech at the luxury Alpine Ski resort.
“Fear and doubt is not a good thought process because this is a time for tremendous hope and joy and optimism and action.”
He added: “To embrace the possibilities of tomorrow, we must reject the perennial prophets of doom and their predictions of the apocalypse.”
In the latest to and fro between the pair, Ms Thunberg said her speech addressed the empty words and promises from world leaders.
She added: “You say children shouldn’t worry... don’t be so pessimistic and then, nothing, silence.”
The activist also referenced the US without naming the country, after Mr Trump withdrew America from the Paris climate agreement and published policies that critics have claimed weakens environmental standards.
“We need to start listening to the science, and treat this crisis with the importance it deserves,” she said.
“Without treating it as a real crisis we cannot solve it.”