US Secretary of State John Kerry on Sunday urged the world to ramp up action on climate change, saying in India that changing weather patterns posed major costs to the planet.
"Here in India, the home of so much of the history of science, we must recognise that today the science of climate change is screaming at us for action," Kerry said in a speech in New Delhi.
After expressing his condolences for the victims of devastating floods in northern India, Kerry said that "it appears as if, in many ways, in many places, Mother Nature is telling us to heed the warnings".
Speaking ahead of a major speech on climate change by US President Barack Obama later this week, Kerry said that India was "well aware of the grave threat this global crisis poses".
"Yours is already one of the most severely affected nations - and unfortunately, the worst consequences of the climate crisis will confront people who are least capable of coping with them," he added.
India, like other emerging economies, has resisted pressure from the West to sign up to targets on cutting carbon emissions.
Kerry said he understood India's "paramount commitment to development and eradicating poverty" but that failure to act decisively on climate change would undermine growth.
"The good news is that if we do this right, it won't hurt our economies - it will grow them," he said.
"It won't deny our children opportunity - it will create new ones. The new energy market can be the biggest on earth, a $6 trillion market with four billion users - and its fastest growing segment, by far, is clean energy."
Kerry was speaking on the first day of a three-day visit to India which will see him hold talks with Prime Minister Manmohan Singh on Monday.