Hello and welcome to NewsHour from the BBC World Service coming to you live from London.

I'm Sean Lay.

Climate negotiations in Baku, Azerbaijan have reached a critical stage, but a resolution of the main sticking point,

how much wealthier nations should pay poorer ones to help them respond to climate change

does not appear in sight. It's the early hours of Sunday morning there, and negotiators from

the nearly 200 countries who signed up to the Paris Climate Treaty are still talking. It's not

unusual for the annual conference of the parties, or cop as it's known, to go to the wire, or even

past it. Earlier, the BBC's climate editor, Justin

Rowlatt, caught up with some of the negotiators as they scuttled from room to room to try to get

a sense of what's holding up a deal.

Where a day over the deadline for an agreement and the representatives of dozens of the world's least developed

countries have just stormed out of a key meeting. Cedric Schuster of Samoa represents the world's

small island states. We just walked out. We came here to this cop for a fair deal. We feel

that we haven't been heard and there's a deal to be made and we are not

been consulted. There is real anger here. Mohamed Addao speaks for African nations. We need to hold

the historic politas accountable for the crisis of course and we cannot let the grid escape that they're actually planning in Baku.

Baku will be remembered as a place that betrayed the world.

John, how's it going?

Poor countries want more cash.

Richer nations say they'll keep talking.

John Podesta is the U.S.'s climate envoy.

I'm hoping this is the storm before the calm.

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