COPENHAGEN — Blocs of countries pitched competing visions for a deal at the U.N. climate talks on Thursday as the early arrival of environment ministers stoked pressure for an outcome. But more problems marred the marathon negotiations, as efforts to chisel out consensus was delayed by a request tabled by Pacific island nation Tuvalu that has split developing nations.

Outside Copenhagen, the Kremlin announced Russian President Dmitry Medevdev would join around 110 other heads of state and government for the grand climax on Dec. 18, while France signaled it would push its European partners to deepen their carbon cuts.

Rival papers tabled by African countries, small island states, emerging giant economies, and conference chair Denmark jockeyed for a place in a draft compromise. They set down varying targets on curbing greenhouse gases that fuel global warming and funding for poor countries so that they can meet this potentially mortal threat. The next step will be to hammer these texts into a workable blueprint for haggling next week.

“This is a three-layer cake: we started, then our ministers take over, then ours leaders take over,” said Dessima Williams of Grenada, who also represents the Associations of Small Island States (AOSIS).

Reflecting divisions, a row dividing poorer nations rumbled on, badly delaying work in a key negotiation pools.

Tuvalu — population 10,000 — pressed a demand that the conference discuss its idea that emerging giant economies be tied to binding emissions cuts under a new round of pledges under the Kyoto Protocol. The proposal drives at the heart of a nearly two-decade-old axiom that only rich nations, and not poor ones, should commit to legal curbs on fossil-fuel pollution.

Underpinning Tuvalu’s demand is that island states and other highly vulnerable nations could be devasted by warming inflicted by uncontrolled emissions from China, India, and Brazil.

Friction was also visible between China and the United States, respectively the world’s No. 1 and No. 2 polluters, whose positions are central to any deal in Copenhagen. China said countries like the U.S. had a duty to pay out billions of dollars in compensation to poorer, developing countries. 

But a U.S. official said China would not be at the top of any U.S. list of countries receiving support to cope with the effects of global warming, a U.S. official said. “The Chinese have enormous capacity,” U.S. negotiator Jonathan Pershing told AFP on Thursday. “If you think about what will be prioritized in terms of the needs of the community for most of the countries, the poorest countries, the countries that are hardest hit — I wouldn’t start with China,” he said.

U.N. climate chief Yvo de Boer said, though, that the mood had improved since the start, which was rocked by finger-pointing over burden-sharing. “I sense there is a real seriousness now to negotiate. Good progress is being made in a number of areas, perhaps especially in the area of technology, which has been of great importance to developing countries,” he told reporters.

If all goes well, the deal will be endorsed by all 194 nations of the U.N. Framework Convention on Climate Change.

Those attending the Copenhagen summit include U.S. President Barack Obama, Premier Wen Jiabao of China, Indian Prime Minister Manmohan Singh, Brazilian President Luiz Inacio Lula da Silva. and the heads of the European Union.

Further talks will be needed next year to flesh out the details of what will in essence be a political accord.

Leaders of the 27-nation E.U. met in Brussels on Thursday for a two-day summit where they were expected to debate the option of deepening a unilateral cut of 20 percent to 30 percent if they found a similar effort among other industrialized countries. French President Nicolas Sarkozy will strive for an E.U. cut of 30 percent cut “as soon as possible”, his environment minister, Jean-Louis Borloo, said in Paris on Thursday.

Spread the news on what the føck is going on in Copenhagen with friends via email, Facebook, Twitter, or smoke signals.