Mukhtar Babayev offered little concrete detail about how to broker this new deal but said climate finance would be a "pillar" of the COP29 summit in the petro-state of Azerbaijan in November.

"We know that the world needs to increase the overall flow of climate finance by several multiples. We must address the issues that hold the developing world back from their full ambitions," Babayev said in a speech in Berlin.

"At COP29, we need to agree a new climate financial goal."

Disagreements over climate aid have dogged past COP negotiations, with richer nations most responsible for planet-heating pollution criticised for not coughing up their fair share.

Just a fraction of the money needed to fund clean energy and build resilience to extreme weather in less developed countries is raised each year, eroding much-needed trust between countries.

Wealthy nations likely only met a previous climate finance pledge of $100 billion for the first time in 2022 -- two years behind schedule, according to the OECD.

But this is far from the estimated $2.4 trillion annually that developing countries -- excluding China -- will need to meet their climate and development needs.

- Short on detail -

Babayev, a former executive of Azerbaijan's national oil giant, acknowledged the issue had been one of the thorniest in climate negotiations and "there are strong and well-founded views on all sides".

He assured they were listening to the concerns of all parties but stressed there was "no single initiative that will unlock climate finance and deliver the multiples we need".

"We need to agree a new climate finance goal, strengthen global financial institutions, put capital into the transition, unlock all mechanisms to support climate action, and increase and speed up concessional finance and philanthropy," he said.

But he did not outline a detailed timeline, financial targets, or other concrete steps that might help overcome the long-running deadlock in the months before COP29.

The push for a pact on financial aid comes as nations are individually being urged to commit to greater climate action.

By early 2025, nations are to explain what steps they are taking to cut emissions in line with the Paris agreement to limit global warming to 1.5 degrees Celsius above the pre-industrial level.

- 'The world has changed' -

The world is nowhere near meeting this target, and some developing countries want their new climate plans contingent on financial aid.

India, for example, proposed that developed countries provide $1 trillion in climate finance every year from 2025 -- 10 times the current target.

But some countries also want a broader pool of contributors to chip into the fund.

Under a UN climate treaty signed in 1992, only a small handful of high-income countries were required to pay for climate finance, and China was not among them.

Today, China is not only far wealthier but the world's largest polluter, and some are pushing for Beijing to pay its share.

"The world has changed, obviously, since 1992," said Germany's Foreign Minister Annalena Baerbock on Thursday, without mentioning China by name.

"This is why I strongly urge those who can to join our effort, and particularly the strongest polluters of today, particularly looking also at the G20."

Earlier this month, UN climate chief Simon Stiell said G20 nations must "rise to this moment" by massively stepping up financial aid for poorer nations least responsible yet most impacted by global warming.