By Kate Abnett, Nailia Bagirova and Karin Strohecker

BAKU (Reuters) - Countries at the COP29 climate summit were warned on Wednesday that the "hardest part" was about to start in talks over how much money should be provided to developing countries to help them cope with climate change.

Figuring out what form that funding takes, who pays and how much is the main task of this year's annual U.N. climate talks. With a notional Friday deadline looming, frustration over the lack of progress was starting to seep out of the negotiating rooms.

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Yalchin Rafiyev, the chief negotiator of the summit's host Azerbaijan said "now the hardest part begins" ahead of a fresh text which is due to drop at midnight (2000 GMT) in the capital Baku.

Progress at the annual summit is typically marked through regular draft documents that get whittled down to a final deal.

COP29 Lead Negotiator Yalchin Rafiyev attends a press conference during the United Nations climate change conference COP29 in Baku, Azerbaijan November 20, 2024. REUTERS/Maxim Shemetov

Wealthy and developing countries are sharply divided over the size of the new goal. It will replace a 2020 pledge by developed countries - delivered two years late - to provide $100 billion per year in climate finance.

Uganda's Adonia Ayebare, who chairs the G77 and China group of more than 130 developing countries, said its demand was for wealthy nations to provide $1.3 trillion in public climate finance per year.

"The frustration is that the other side has not given us a counter offer," Ayebare told Reuters.

"We are hearing $300 billion. But if that is true, that's really not acceptable. It's embarrassing," he said.

Another developing country negotiator told Reuters the European Union had floated $200 billion or $300 billion in informal talks. But on Wednesday, the EU maintained it did not have an official position on the number.

(REUTERS/Angus Mordant/File Photo)

EU climate commissioner Wopke Hoekstra said the bloc was not willing to talk about the figure until it had more structural details, adding: "Otherwise you will have a shopping basket with a price, but you don't know exactly what is in there".

Countries are still at odds over whether large, still-developing economies - including the world's second-biggest economy China - will contribute towards the goal.

Egypt's Minister of Environment, Yasmine Fouad, said countries had agreed better off developing nations would not be legally obliged to pay in.

Azerbaijan's Rafiyev said the COP29 presidency would produce a tighter text overnight. In simple terms, a 25-page document stuffed with multiple options for almost every paragraph needs to become a two page document that can be refined in the final days and then adopted.

"We will have shorter, more concise, straight to the point, texts," Rafiyev said.

Fossil fuels

While talks on finance have been slow, those on speeding up efforts to cut climate-damaging emissions are proving as tough.

After agreeing a landmark deal to transition away from fossil fuels in Dubai last year, countries had so far failed to agree on language that would take that work forward in Baku.

A man stands next to the logo of the COP29 United Nations climate change conference, in Baku, Azerbaijan November 20, 2024. REUTERS/Maxim Shemetov/File Photo

Austria's climate minister Leonore Gewessler told Reuters the Arab group of countries led by Saudi Arabia had been "very vocal in watering down the mitigation part" of negotiations.

A representative for Saudi Arabia's delegation did not immediately respond to a request for comment.

Saudi Energy Minister Prince Abdulaziz bin Salman has previously described the Dubai deal as a menu of options - suggesting not all countries will select quitting fossil fuels as their chosen path forward.

OPEC Secretary General Haitham Al Ghais used a speech at the summit to say crude oil and natural gas were a gift from God, echoing words of Azerbaijan President Ilham Aliyev, whose opening speech hit out at Western critics of the industry.

Getting a fresh commitment on cutting emissions more quickly has been thrown into sharp relief by a growing belief among scientists that the world's aspirational goal of limiting global warming to 1.5 degrees Celsius could soon be beyond reach.

Recent trends, if not changed, "will drive us to crossing 1.5 in the early 2030s or even slightly before", said French climatologist Robert Vautard.

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(Reporting by Kate Abnett, Nailia Bagirova, Karin Strohecker and Gloria Dickie; Writing by Simon Jessop; Editing by Alexander Smith and Ros Russell)

Thumbnail courtesy of REUTERS/Maxim Shemetov/File Photo.