COPENHAGEN (AFP) - A leaked Danish proposal triggered outrage at Copenhagen climate talks, with developing nations condemning a draft deal that they argued would consign most of the world's poor to permanent penury.

The "draft political agreement" circulated informally by the host government exposed the deep faultlines besetting a 192-nation conference aimed at averting the potential planetary catastrophe of global warming.

The cost of failure in Copenhagen was underlined by the UN's World Meteorological Organisation, which said the current decade was shaping up to be the hottest since accurate records began in 1850.

However, the G77 group of emerging nations denounced the Danish text as a backroom stitch-up that favoured rich countries on the pivotal issues of emissions curbs and financing to combat climate change.

The text is a "serious violation that threatens the success of the Copenhagen negotiating process", said Sudanese envoy Lumumba Stanislas Dia Pin, who heads the G77 bloc including top polluter China and India.

"The G77 members will not walk out of this negotiation at this late hour because we can't afford a failure in Copenhagen," he told journalists.

"However, we will not sign an unequitable deal. We can't accept a deal that condemns 80 percent of the world population to further suffering and injustice."

The Danish draft, seen by AFP, states the conference's parties have a "shared vision" for limiting warming to a maximum of two degrees Celsius (3.6 degrees Fahrenheit) above pre-industrial times.

Emissions pledges are not detailed but, among other things, the draft points to a year by which developing countries, which are the big emitters of tomorrow, would see their emissions reach a maximum.

Chinese negotiator Su Wei said he had not seen the text, but added: "It is too early to talk about a peak year for developing countries."

The text also makes no mention of extending post-2012 commitments under the Kyoto Protocol, which mandates emissions curbs for developed nations but does not impose legally binding action on poorer economies.

"Like ants in a room full of elephants, poor countries are at risk of being squeezed out of the climate talks in Copenhagen," said Antonio Hill of Oxfam International.

Developing countries, several of which are already big polluters, are refusing to budge unless rich nations slash their emissions by at least 40 percent by 2020 over 1990 levels.

And rich countries are under pressure to kick in 10 billion dollars a year in "fast-track" funding from 2010 to 2012 to transfer anti-warming technology and expertise to poorer ones.

UN climate chief Yvo de Boer and Danish conference chairwoman Connie Hedegaard sought to still the ruckus, insisting the text dated November 27 was informal and simply aimed at sounding out opinion.

"Under no circumstances is this a 'secret Danish draft' for a new climate change agreement. Such a text does not exist," Hedegaard said, stressing that multiple negotiating papers would be "used for testing various positions".

UN chief Ban Ki-moon said earlier he was "optimistic" that the 12-day negotiations climaxing in a summit of some 110 world leaders would yield a "robust agreement".