A new round of U.N. climate talks began Monday in Bonn, Germany, three months before world governments are supposed to adopt a historic agreement to combat global warming.
The climate accord envisioned for Paris in December will be a test for the diplomatic process, which failed to create a strong deal six years ago in Copenhagen.
U.N. officials say the outlook is more positive now because most major economies already have presented national plans to limit their emission of climate-warming gases after 2020, when the new deal is intended to take effect.
Still, much work remains on how to ensure that countries abide by their pledges and how to divide the responsibilities of climate action among developed and developing countries, officials say.