DURBAN - After 12 days of wrangling, UN climate talks went into extra time Friday with China, the US and India under pressure to back a European bid for a new worldwide pact on greenhouse gases.
But the outcome remained unpredictable, with scenarios ranging from limited progress to a lowest-common-denominator deal -- or a diplomatic bust-up.
A core group of about two dozen ministers, representative of rich and poor countries alike, was expected to haggle into the night.
Assuming they found common ground, their compromise would be put to a plenary of the 194-nation UN Framework Convention on Climate Change (UNFCCC) on Saturday.
On the table is a European scheme which the EU claims is backed by nearly two-thirds of the world's nations.
The plan calls for a "roadmap" leading to a global accord, to be negotiated by 2015, which for the first time would bind all nations to legal commitments to tackle greenhouse gases.
Rallying around the European proposal are the least developed countries, the African bloc, small island states and Brazil and South Africa, said European Climate Commissioner Connie Hedegaard.
This left the United States, China and India to declare their hand, she indicated. The US and China are the world's biggest emitters.
"The success or failure of Durban depends on the small number of countries who have not yet committed to the roadmap and the meaningful content that it of course must have," said Hedegaard.
A compromise text put by South Africa to the core group was given a verbal lashing, prompting the chair to agree that a second draft was needed, according to a European diplomat.
Supporters of the roadmap dismissed the first text as worthless fudge.
They said it lacked the key words "legally-binding" and implied the pact -- which it described as a "framework" -- would take effect only after 2020.
"We will put the world in a process to be cooked," Bolivian delegation chief, Rene Orellana, head of the left-leaning Latin American ALBA group, told reporters.
"This is the death of climate," Orellana said in English.
Karl Hood, environment minister of Grenada and chairman of a 43-nation bloc of small island states, told AFP: "It is difficult for us to accept that you start a new process at the end of this that will finish in 2015, and doesn't become operational until after 2020. We are looking at God-only-knows when."
The roadmap seeks to beef up multilateral action in the coming decade, when scientists say carbon emissions that are driving the planet to worsening floods, drought, rising seas and storms, must peak.
The goal is to bridge the gap between the end of 2012 -- when the first round of legal-binding curbs commitments under the Kyoto Protocol expire -- and 2020, the date up to which countries have made voluntary pledges on carbon reductions.
Those pledges, scientists say, fall far short of what is needed to prevent the planet from heating up by more than 2.0 degrees Celsius (3.6 degrees Fahrenheit) beyond pre-industrial levels, the UN-embraced threshold for dangerous warming.
Beijing has said it is not opposed to taking on binding commitments after 2020, but tied that offer to a long list of conditions.
US negotiators, acknowledging a difficult domestic political context, have shied away from signing on to anything with the label "legally binding."
"China has been blowing hot and cold. If it throws its weight behind the EU position it would put pressure on the US to follow suit," said Thomas Spencer, a climate policy analyst from the Institute for Sustainable Development and International Relations (IDDRI) in Paris.
Under the EU deal, Europe would sign up to a second round of Kyoto promises, thus satisfying developing countries clamouring to keep the landmark treaty alive.
As the talks went into extra time, the environment minister of the Maldives, Mohamed Aslam, joined several hundred green activists in a protest rally that blocked the main hallway outside the plenary venue.
UN security guards peacefully dispersed the protest, expelling around two dozen people, including Greenpeace International head Kumi Naidoo.