Nearly 200 nations hammered out a legally binding deal to cut back on greenhouse gases used in refrigerators and air conditioners, a Rwandan minister announced to loud cheers on Saturday, in a major step against climate change.
The deal, which includes the world's two biggest economies, the United States and China, divides countries into three groups with different deadlines to reduce the use of factory-made hydrofluorocarbon (HFC) gases, which can be 10,000 times more powerful than carbon dioxide as greenhouse gases.
"It's a monumental step forward," U.S. Secretary of State John Kerry said as he left the talks in the Rwandan capital of Kigali late on Friday.
As Rwanda's Minister for Natural Resources, Vincent Biruta, began spelling out the terms of the deal shortly after sunrise on Saturday, applause from negotiators who had been up all night drowned out his words.
Under the pact, developed nations, including much of Europe and the United States, commit to reducing their use of the gases incrementally, starting with a 10 percent cut by 2019 and reaching 85 percent by 2036.
Many wealthier nations have already begun to reduce their use of HFCs.
Two groups of developing countries will freeze their use of the gases by either 2024 or 2028, and then gradually reduce their use. India, Iran, Iraq, Pakistan and the Gulf countries will meet the later deadline.
They needed more time because they have fast-expanding middle classes and hot climates, and because India feared damaging its growing industries.
"Last year in Paris, we promised to keep the world safe from the worst effects of climate change. Today, we are following through on that promise," said U.N. environment chief Erik Solheim in a statement.