A dispute about how to link greenhouse-gas emissions cuts to a promise from the wealthiest nations for $100 billion a year in climate aid emerged as a major stumbling block at UN talks on global warming.
After a week of discussions in Bonn, envoys from some 190 nations deadlocked about the formula countries will use in setting out their commitments on reducing fossil-fuel pollution in time for the deal they plan to sign in Paris in 2015.
