The world must immediately and drastically cut fossil fuel emissions to avert the most catastrophic effects of climate change, United Nations Secretary-General Antnio Guterres said Friday at his final climate summit, urging the world to "follow the science" and face hard facts.

"You cannot build peace on a burning planet," Guterres told reporters, stressing that climate change is central to the U.N.'s work because it contributes to geopolitical instability by driving hunger and displacement, pushing countries into debt and fueling competition for land and water.

"You cannot eradicate poverty when climate disasters keep throwing people back into it," he added.