UN chief Antonio Guteress again cited the deadliest floods in a century in Kerala to highlight the grave consequences of inaction over climate change.

Guteress also referred to hurricane Maria that killed almost 3,000 people in Puerto Rico last year, making it one of the deadliest extreme weather disasters in the United States history.

“Climate change is the defining issue of our time – and we are at a defining moment. We face a direct existential threat. Climate change is moving faster than we are – and its speed has provoked a sonic boom SOS across our world,” he said in a landmark speech on climate action at the United Nations on Monday.