Hope for climate talks' final hours
Negotiators were preparing for a long final session at the National Stadium in Warsaw as UN talks on climate change crawled to a conclusion.
A new draft of a key text was produced early on Friday morning and was being revised and amended during the day.
One participant told the BBC that the nature of these talks was that progress was only made in the final hours.
Campaigners who walked out on Thursday said the meeting was on the point of delivering "virtually nothing".
Seyni Nafo from Mali, the spokesman for the Africa Group of countries, said he was ready for the long haul.
"I am prepared to leave here on Sunday, but this is what we are here for and this is when it happens right at the very last moment," he said.
Mr Nafo said the issue of loss and damage which had created great divisions between the parties and sparked a walkout was edging towards a compromise.Sticking point
The developing nations are looking for a new institution with legal and executive powers that would compensate people for loss and damage caused by extreme weather events, exacerbated by global warming. Richer countries want it to be dealt with within the existing institutions.
End Quote Ed Davey UK Climate Secretary
We have a little bit more to do before we can say we've got what we needed”
"We're trying now to bridge those two and really see if there can be a two-step approach starting with co-ordinating the already existing framework and seeing how we can enhance that in a second phase but that needs to be captured in a decision," said Mr Nafo.
A new text outlining how a global agreement might be shaped was released early on Friday. The ad hoc working group on the Durban Platform (ADP) is an attempt to outline the steps to a new deal in Paris in 2015.
But it is held up over agreement on a timeline in which people have to declare their emissions cuts for the 2015 agreement and the level of those cuts.
One of the green groups that decided not to walk out of the talks said that the text lacked "ambition".
"The latest draft of the ADP text, which outlines a roadmap towards agreeing a new climate deal in 2015, still has some glaring gaps," said Sven Harmeling, climate change advocacy coordinator at CARE International.
"As it stands, it risks locking in low ambition."'Considerable' challenge
But UK Climate Secretary Ed Davey said that the text was going in the right direction. Mr Davey is one of the EU representatives in the ADP negotiation.
"The ADP is getting in a better place, some of the things we wanted to see are there. It's critical for going forward, we are seeing progress, but we have a little bit more to do before we can say we've got what we needed," he said.
Mr Davey said the issue of measuring, reporting and verifying (MRV) the level of emissions cuts had now been agreed, at least for the period up to 2020.
"We've not ever had an agreement on MRV that covers developing countries previously. But we've got that framework now and that's the sort of nuts and bolts we really needed to bring and get agreement on at this COP," he said.
But China's lead climate negotiator Su Wei said: "The Warsaw talks, which should have been an important step forward... are now on the verge of delivering virtually nothing."
Meanwhile the UN confirmed that Paris would host the 2015 meeting at which a global deal is expected to be signed. It will be held at Le Bourget on the northern edge of the French capital. Speaking in Warsaw, French foreign minister Laurent Fabius told news agencies that the "challenge was considerable".
"It is not supposed to be a conference that is a testbed, but a conference for making decisions, and the best way to prepare for it will be to advance as far as possible at Warsaw and (in 2014) in Lima."
Follow Matt on Twitter