BONN, Germany (AP) — U.N. climate talks are plodding ahead toward a worldwide deal to fight global warming, with negotiators agreeing to start work on a draft agreement.

A weeklong session in Bonn finished Friday with the two officials leading the talks getting the green light to turn a sprawling negotiating text into a more coherent draft by the next round of talks in October. The deal is expected to be signed in Paris in December.

A host of key issues still need to be resolved, including how to share the burden of slashing climate-warming carbon emissions and helping poor countries adapt to rising sea levels and other impacts of global warming.

Most major economies have already presented their plans to limit climate-warming carbon emissions after 2020, when the Paris deal is to take effect.