Climate summit failure looms, leaders warn

World leaders warned Thursday that the UN climate summit was heading for failure amid a deep rift over sharing the burden of carbon-emissions cuts and paying for the defence against global warming.

French President Nicolas Sarkozy warned of a looming disaster, while the United States insisted it would be better to leave Copenhagen with no deal rather than a bad one.

"There is less than 24 hours. If we carry on like this, it will be a failure," Sarkozy warned angrily from the conference podium. "Failure at Copenhagen would be catastrophic for all of us."

The European Union called for an emergency meeting of "relevant players" late Thursday in a bid to break the deadlock.

More than 120 leaders, including US President Barack Obama, are due to attend the summit on Friday, but few at Copenhagen's Bella Center held out hope of a deal that could transform the 12-day parlay into a triumph.

"Coming back with an empty agreement would be far worse than coming back empty-handed," said White House spokesman Robert Gibbs before Obama left Washington.

US Secretary of State Hillary Clinton accused developing nations -- without naming them -- of backsliding on pledges to open their promised controls on carbon emissions to wide scrutiny.

The question is "a deal-breaker for us," she said.

China and India say they are willing to take voluntary measures to slow their surges in heat-trapping greenhouse-gas emissions.

But they are reluctant to accept tough international inspection and insist rich nations shoulder the main burden by accepting huge reduction targets.

"We should not continue to dwell on these issues that are dividing us. We should narrow our differences, otherwise we are facing a failure," Chinese Vice Foreign Minister He Yafei told reporters.

The sole glimmer of hope in the darkening mood was progress on funding to help poor countries menaced by climate change.

Clinton announced Washington would contribute to a 100-billion-dollar annual fund through 2020 to help poor nations -- but provided an ambitious overall deal was completed in Copenhagen.

The G77, the major bloc of developing countries, said the US proposals were "a good signal" but still not enough.

A mountain of work needed to be done with little more than a day to go, and there were rumours the talks would run into the weekend.

The European Union called for all parties "to urgently go to the outer limits of their flexibility" so that talks could advance.

Ban Ki-moon, the UN secretary general, tried to talk up the prospects of an agreement, saying he had "not seen anything that indicates we cannot seal a deal."

"There are more than 130 leaders here. If they cannot seal a deal who can?"

After earlier expressing doubt that the summit would pin down an agreement to cap global warming at two degrees Celsius (3.6 Fahrenheit), German Chancellor Angela Merkel said leaders could forge a deal but added that "we will not be able to work out all the little details".

An internal UN memo seen by AFP showed national pledges for reducing greenhouse gas output so far proposed would set the planet on a course for a 3.0 jump in global temperatures compared to pre-industrial times.

Scientists say such a rise would be disastrous, condemning hundreds of millions of people to worsening drought, floods and storms.

The United States was widely condemned for foot-dragging on climate change under President George W. Bush, and Obama is hoping his presence at the finale will be evidence of a transformation of policy.

EU Commission chief Jose Manuel Barroso said he expected Obama to announce further US action to push things forward "because if they don't do it, others will find an excuse also not to move."

However a senior Obama administration official said he did not expect the president to unveil more specific commitments on financing.

1. The Climate Pool