The UAE's COP28 president says there is no science to show that phasing out fossil fuels would achieve the world's climate goals, but acknowledges that it is "inevitable", a report said on Sunday.

Sultan Al Jaber — who also heads state oil giant ADNOC — made the comments during a testy exchange with former Irish leader Mary Robinson during an online forum, a video published by The Guardian showed.

The 50-year-old, who is also the United Arab Emirates' climate envoy, added that removing fossil fuels would take the world "back into caves".

"I'm not in any way signing up to a discussion that is alarmist," Jaber told the SHE Changes Climate online conference on November 21.

"I am factual and I respect the science, and there is no science out there, or no scenario out there, that says that the phase-out of fossil fuels is what's going to achieve 1.5."

The landmark 2015 Paris Climate Conference outlined the goal of restricting global warming to 1.5 degrees Celsius above pre-industrial levels to avoid catastrophic environmental fallout.

A United Nations assessment of climate pledges released last month found the world was way off-track in hitting this target.

"1.5 is my North Star and a phase-down and a phase-out of fossil fuels in my mind is inevitable, it's essential," Jaber told the forum on women leading climate action. 

"But we need to be real, serious, and pragmatic about it."

He added: "Show me a roadmap for a phase-out of fossil fuels that will allow for sustainable socio-economic development unless you want to take the world back into caves."

Attempt to undermine

Specifying a "phase-out" or weaker "phase-down" of fossil fuels is one of the main battles facing negotiators at COP28 in Dubai, where they will try to reach a new agreement to deal with global warming.

Jaber has repeated since June that phasing out hydrocarbons is inevitable, but that it cannot happen before viable alternatives are in place — and that developed nations must lead the way.

A COP28 spokesperson said the report was "just another attempt to undermine the presidency's agenda, which has been clear and transparent and backed by tangible achievements by the COP president and his team.

"The COP president was unwavering in saying reaching 1.5C involves action across several areas and sectors. The COP president is clear that phasing down and out of fossil fuels is inevitable and that we must keep 1.5C within reach."

Joeri Rogelj, professor of climate science and policy at Imperial College London, said last month's report by the UN's IPCC climate change panel backed a phase-out.

"I strongly recommend (Jaber) asking around for the latest IPCC report," he said.

"That report, approved unanimously by 195 countries including the UAE, shows a variety of ways to limit warming to 1.5C — all of which indicate a de facto phase-out of fossil fuels in the first half of the century."