"Ecosystems are dying, we are at the gates of a mass extinction," added the 16-year-old activist who accused world leaders of looking the other way or thinking only of money.

"Sad and angry," with a long braid and a pink blouse, Greta started the message personally, ensuring that today she should not be at the UN speaking on behalf of young people but should be in school, on the other side of the ocean.

"They have stolen my dreams, my childhood with his empty words," he said before adding that "however, I am lucky, because (unlike her) there are many who suffer, those who are dying" because of global warming .

Greta, who has inspired millions of young people throughout the world, insisted that for more than thirty years "scientific data is very clear" about the climate crisis and its devastating consequences.

"How dare they look the other way, to come here to say that they are doing enough. They say they listen to us, that they understand the urgency but ... if they really understood the situation they would not be doing nothing," he said before point ironically: "I don't want to believe that they don't act out of evil."

Greta said that the proposal to reduce pollutant emissions by half to prevent the planet's temperature from rising above 1.5 ° C is not ambitious enough.

"It is not acceptable for us, because we are what we are going to have to live with these consequences," he said before stressing: "We are failing young people, but young people are understanding the magnitude of their betrayal. (...) The new generations are waiting for you and if you fail we will never forgive you. "