Sharm el Sheikh (Egypt) (AFP) - UN climate talks were extended by a day Friday in an effort to break a deadlock as nations tussle over funding for developing countries battered by weather disasters and ambition on curbing global warming.

Representatives from nearly 200 countries have gathered at the COP27 in Egypt for two weeks with the aim of driving forward action on climate change as the world faces a worsening onslaught of weather extremes.

But wealthy and developing nations struggled to find common ground on a host of crucial issues, as the summit in the Red Sea resort of Sharm el-Sheikh spilled into overtime.

Egyptian Foreign Minister Sameh Shoukry, who chairs the COP27 talks, told delegates that the negotiations would go into Saturday.

“I remain concerned at the number of outstanding issues,” he said.

The daunting list of tasks includes finding agreement on emissions cutting ambitions and reaffirming a goal to limit average warming to 1.5 degrees Celsius from pre-industrial levels, which scientists say is a safer guardrail to avoid the most dangerous impacts.

Rich countries are also under pressure to finally fulfil promises to provide $100 billion a year to help developing countries green their economies and adapt to future impacts.

But for many vulnerable countries the defining issue at the conference is money for the “loss and damage” caused by climate change – a controversial issue previously blocked by wealthy countries fearful of open-ended liability.

- ‘Crunch time’ -

A cascade of climate-driven extremes in recent months – from floods in Pakistan and Nigeria to heatwaves and droughts across the world – have shone a spotlight on the ferocious impacts of a warming world for emerging economies, as well as small island states threatened by sea level rise.

The G77 and China bloc of 134 developing countries launched an opening gambit this week, with a proposal to create a loss and damage fund at COP27, with operational details to be agreed later.

A compromise response from the European Union, proposed late Thursday, suggested a fund specifically for the most vulnerable nations.

But one key country, the United States, has remained discreet.

“It’s crunch time,” Rachel Cleetus, lead economist at the Union of Concerned Scientists’ climate programme, told AFP. “There’s no time anymore for the US to sit on the sidelines.”

A US State Department spokesperson declined to comment, citing ongoing negotiations.

Cleetus said the US and China, the world’s two biggest polluters, “can really unlock this” in view of a thaw in climate relations following a meeting between Presidents Joe Biden and Xi Jinping earlier this week in Bali.

Cleetus added China should also make its position clear, particularly on the issue of whether it would contribute to such a fund and pledge not to draw from it.

- ‘Our final offer’ -

European Commission Vice President Frans Timmermans told reporters on Friday that the EU offer had two “very important” conditions that differ from the G77 proposal.

It should be for “the most vulnerable” nations, he said, and the money should come from a “broad funder base” – code for countries including China that have become wealthier since they were listed as developing nations in 1992.

“I have to say this is our final offer,” Timmermans said.

Canadian Environment Minister Steven Guilbeault told reporters countries were “close” to an agreement but that “the funds should include all large emitters, which would include a country like China, and Saudi Arabia and Qatar”.

Pakistan’s climate minister Sherry Rehman, whose country chairs G77+China, expressed a willingness for “working with each other to find common ground”.

“It is up to all of us to steer a path that sends a powerful message from this COP,” she said.

She said the G77 had zeroed in on one of the options put forward in a draft loss and damage text “with a few changes that have been submitted and we are working on with each other”.

Timmermans said he had explained the EU proposal to US delegates who were “very interested in seeing” the 1.5C target reaffirmed.

Vulnerable nations and many wealthy emitters have stressed the need to maintain the 1.5C goal, while observers are calling for stronger language in the final COP27 statement on curbing planet-heating fossil fuels.

Even with new commitments, the world is on track to heat up by about 2.5C by the end of the century – enough, scientists say, to trigger dangerous climate tipping points.

With tight restrictions on demonstrations, several dozen activists on Friday protested inside the venue, holding signs demanding rich countries “pay up for loss and damage”.