When Greta Thunberg, a 15-year-old climate activist from Sweden, had the chance to address a global climate change conference this past week, she told officials she had not come to beg.
"You have ignored us in the past, and you will ignore us again," she said.
But she warned them that "you say you love your children above all else, and yet you are stealing their future in front of their very eyes".
The teenager's remarks quickly gained attention on social media, and was shared by leading climate scientists and some elected officials. US Senator Bernie Sanders tweeted footage of her speech, saying she "called out world leaders for their global inaction on climate change".
Greta accused leaders of only speaking about "green eternal economic growth because you are too scared of being unpopular".
"You only talk about moving forward with the same bad ideas that got us into this mess even when the only sensible thing to do is pull the emergency brake," she said. "You are not mature enough to tell it like it is."
She spoke on behalf of Climate Justice Now!, a global network of climate advocacy groups.
Officials from nearly 200 countries gathered in Poland over the past two weeks to "nudge the world toward stronger targets for reducing carbon emissions and enshrine a clearer set of rules for how to get there".
Greta has already spent years working as a climate activist.
She garnered attention this year when she went on strike from school, holding a sign outside the Swedish parliament building in Stockholm that said "school strike for climate". The New Yorker reported that she spent three weeks sitting in front of parliament during school hours, and later returned to school four days a week, but continued to spend Fridays protesting.
The jury for the Children's Climate Prize wrote that she was nominated as a finalist this year because she had "shown more determination, dedication and strength in combating climate change and working for the future of humanity than most adults or politicians ever do".
But on Twitter, Greta asked to be removed from the list of finalists, noting that many would have to fly to the awards ceremony. "All finalists are to be flown in from all over the world, to be a part of a ceremony, has no connection with reality," she wrote. "Our generation will never be able to fly (among other things), other than for emergencies. Because the adult generations have used up all our carbon budget."