A 13-year-old Indian girl, speaking on behalf of the world's three billion children, asked world leaders here, including the Presidents of United States and China, for urgent action on climate change.

"I am so much concerned about climate change because I don't want our future generations to question us just as I am questioning the need of more concrete action on climate change today," Yugratna Srivastava from Lucknow said at the Summit on Climate Change in the United Nations.