Delegates at the UN climate conference in Durban are expected to work early into Saturday morning in the hope of finding an agreement that all countries feel able to sign.
With the event due to close on Friday, an EU-proposed “roadmap” for climate change is currently on the table, with delegates certain to pull it apart and stitch it back together in the hope of finding a suitable legal framework.
However, the EU package, a global climate change deal extending to 2020, seems to have little chance of gaining a broad agreement in its current form, with India, the US and China unlikely to sign on.
As it stands, the deal would see Europe extend its commitment to reduce emissions under the Kyoto agreement on the condition that all the other nations, including China, the US and India, commit to reaching an agreement on a new and legally-binding treaty by 2015, with reductions to start by 2020.
However, many delegates remain pessimistic about countries putting aside their national interest in favour of the global good.
Speaking to the Association Press on Friday, Connie Hedegaard, the European commissioner for climate action, said: "If there is no further movement from what I have seen until 4 o'clock this morning, then I must say I don't think that there will be a deal in Durban."
Agreement from the US, where the congress is unashamedly hostile to climate change, looks unlikely, especially without agreement from China, Washington's main economic competitor. Likewise, Beijing appears unwilling to agree to reductions that restrict all countries, whether developed or developing.
Under the Kyoto agreement, industrial countries must reduce emissions while developing countries are not legally bound.
Even if an agreement is reached, a roadmap to 2020, followed by a legally binding reduction agreement will prove highly unsatisfactory to activist and campaigners searching for much more immediate cutbacks in emissions.
It will also prove a huge disappointment from those nations already threatened by climate change, particularly the members of the Alliance of Small Island States (Aosis).
Speaking to the BBC, one UN observer said that the current roadmap "buys 10 years' delay in action for the US, China, India and Brazil, and risks making the most vulnerable countries 'road kill' on the big emitters' highway to the future."
Still, Chris Huhne, the energy and climate secretary remained upbeat that a deal would be done. Speaking on Thursday, he said: "A comprehensive global agreement is not beyond our reach. We can achieve it when we display flexibility and the will to compromise."
On Friday, a large group of protesters demonstrated outside the conference building demanding that the delegates find an immediate solution to the negotiations.
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