The latest Cop29 draft deal on climate finance is thought to have been firmly rejected by developing countries as negotiators walked out of UN talks on the verge of collapse.

Negotiators from rich and poor nations were huddled in one room on Saturday as the talks to reach a deal on money for developing countries went into overtime in Azerbaijan, a day after the UN summit was scheduled to finish.

A group of negotiators from the Least Developed Countries (LDC) bloc and the Alliance of Small Island States walked out because they did not want to engage with the rough draft in Baku.

The "current deal is unacceptable for us. We need to speak to other developing countries and decide what to do", Evans Njewa, the chairman of the LDC group, said.

Asked if the walkout was a protest, Colombia environment minister Susana Mohamed told The Associated Press: "I would call this dissatisfaction, [we are] highly dissatisfied."

The last official draft on Friday pledged 250 billion dollars annually by 2035, more than double the previous goal of 100 billion dollars set 15 years ago but far short of the annual one trillion-plus dollars that experts say is needed.

The rough draft discussed on Saturday was for 300 billion dollars, sources told the Associated Press.

Developing countries have accused the richer nations of trying to get their way - and a small financial aid package - via a war of attrition.

Meanwhile, small island nations, particularly vulnerable to climate change's worsening effects, accused the host country presidency of ignoring them for the entire two weeks.