Sultan Al Jaber, president of the COP28 climate talks, called on Saturday for "available, accessible and affordable" finance for the developing economies most vulnerable to the destructive impacts of a warming planet.
Al Jaber, who is also head of the United Arab Emirates' national oil company, said he had urged G7 climate and environment ministers meeting in Japan this weekend to prioritise support for poorer countries.
"The time has come for us to provide a fair deal for the Global South, especially when it comes to climate finance," he told AFP on the sidelines of the G7 talks in Sapporo.
"I'm fine with raising ambitions, even going for more ambitious plans and programmes" to fight global warming, he said.
However, to boost trust worldwide "this needs to be equipped and coupled and supported with real, pragmatic, actionable plans enabled by finance that is available, accessible and affordable".
The choice of Al Jaber, chief executive of the Abu Dhabi National Oil Company (ADNOC), to head December's COP28 UN climate change conference in Dubai has angered activists who fear it will hold back progress on reducing emissions.
Al Jaber, 49, is also the UAE's minister for industry and advanced technology and founded the government-owned renewable energy company Masdar.
COP27, held in Egypt in November, brought a landmark agreement to create a "loss and damage" fund to cover the costs of the destruction that developing countries face from climate-linked natural disasters.
Floods that covered large swaths of Pakistan last year and drought in East Africa both bear the fingerprint of climate change.
Multi-billion-dollar investment plans have also been announced in recent months for countries such as South Africa and Indonesia to transition to clean energy from fossil fuels.
Al Jaber said climate finance for developing countries needs to be "very high on the agenda".
But he highlighted the need "to strike a balance between passion and realism, in order for us to deliver a true, pragmatic, progressive, practical deal at COP28".
In a closed-door address to the G7 climate ministers on Saturday, Al Jaber also called for developed countries to follow through on an unfulfilled promise to provide developing nations with $100 billion a year to fight climate change.
He also urged the world to triple the amount of money available for clean tech investment, adaptation finance and energy transition in developing countries by 2030, according to a transcript of his speech obtained by AFP.
The latest leaked draft of a G7 climate statement to be issued on Sunday reaffirms the bloc's commitment to the $100-billion pledge, which dates back to COP15 in Copenhagen in 2009.
In the draft, the G7 vows to work with other developed nations "to fully meet the goal in 2023".