The new deal clinched at the UN conference in Baku is intended to replace developed countries' previous commitment to provide $US100 billion ($A154 billion) per year in climate finance for poorer nations by 2020. That goal was met two years late, in 2022, and expires in 2025.
Countries also agreed early on Sunday on rules for a global market to buy and sell carbon credits that proponents say could mobilise billions more dollars into new projects to help fight global warming, from reforestation to deployment of clean energy technologies.
The COP29 summit has agreed to inject at least $US300 billion to combat global warming. (EPA PHOTO)
The funding is intended to help developing countries enhance climate protection and adapt to the devastating effects of global warming, such as more frequent droughts, storms and floods.
The $US300 billion will go to developing countries who need the cash to wean themselves off the coal, oil and gas that causes the globe to overheat, adapt to future warming and pay for the damage caused by climate change's extreme weather.
It's not near the full amount of $US1.3 trillion ($A2 trillion) that developing countries were asking for, but it's three times the $US100 billion a year deal from 2009 that is expiring. Delegations said this deal is headed in the right direction, with hopes that more money flows in the future.
"Everybody is committed to having an agreement," Fiji delegation chief Biman Prasad said as the deal was being finalised.
"They are not necessarily happy about everything, but the bottom line is everybody wants a good agreement."
It's also a critical step toward helping countries on the receiving end create more ambitious targets to limit or cut emissions of heat-trapping gases that are due early next year.
It's part of the plan to keep cutting pollution with new targets every five years, which the world agreed to at the UN talks in Paris in 2015.
The Paris agreement set the system of regular ratcheting up climate fighting ambition as away to keep warming under 1.5 degrees Celsius above pre-industrial levels. The world is already at 1.3 degrees Celsius and carbon emissions keep rising.
Countries also anticipate that this deal will send signals that help drive funding from other sources, like multilateral development banks and private sources.
That was always part of the discussion at these talks — rich countries didn't think it was realistic to only rely on public funding sources — but poor countries worried that if the money came in loans instead of grants, it would send them sliding further backward into debt that they already struggle with.
"The $US300 billion goal is not enough, but is an important down payment toward a safer, more equitable future," said World Resources Institute President Ani Dasgupta.
"This deal gets us off the starting block. Now the race is on to raise much more climate finance from a range of public and private sources, putting the whole financial system to work behind developing countries' transitions."
It's more than the $US250 billion ($A385 billion) that was on the table in the first draft of the text, which outraged many countries and led to a period of frustration and stalling over the final hours of the summit.
After an initial proposal of $US250 billion a year was soundly rejected, the Azerbaijan presidency brewed up a new rough draft of $US300 billion, that was never formally presented, but also dismissed roundly by African nations and small island states, according to messages relayed from inside.
The several different texts adopted early on Sunday morning included a vague but not specific reference to last year's Global Stocktake approved in Dubai.
Last year there was a battle about first-of-its-kind language on getting rid of the oil, coal and natural gas, but instead it called for a transition away from fossil fuels. The latest talks only referred to the Dubai deal, but did not explicitly repeat the call for a transition away from fossil fuels.
with DPA and AP
