Negotiators from nearly 200 countries agreed for the first time to establish a fund that would help poor, vulnerable countries cope with climate disasters made worse by the pollution spewed by wealthy nations that is dangerously heating the planet.

The decision regarding payments for climate damage marked a breakthrough on one of the most contentious issues at United Nations climate negotiations. For more than three decades, developing nations have pressed for loss and damage money, asking rich, industrialized countries to provide compensation for the costs of destructive storms, heat waves and droughts fueled by global warming.

But the United States and other wealthy countries had long blocked the idea, for fear that they could be held legally liable for the greenhouse gas emissions that are driving climate change.