G20 under pressure to deliver on climate ahead of UN talks

G20 leaders launched a desperate push Sunday to agree a joint approach to tackling climate change, with officials working through the night to reach a meaningful commitment ahead of UN talks.

The Group of 20 major economies emit nearly 80 percent of carbon emissions, and a promise of action would provide a much-needed boost to COP26 climate talks starting in Glasgow on Sunday.

But draft communiques suggest they would fall short of a firm pledge to keep global warming to 1.5 degrees Celsius above pre-industrial levels or a clear timeline on how to reach net zero emissions.

Experts say meeting the 1.5 degree target -- the most ambitious goal in the 2015 Paris climate deal -- means slashing global emissions nearly in half by 2030 and to "net-zero" by 2050.

Officials in Rome "negotiated the whole night" and into Sunday morning, an EU source said, pressing for something to take to Glasgow, where nearly 200 leaders gather over the next few days.

US President Joe Biden is among those pushing for tough action in Rome, although his own ambitious climate policy is mired by infighting among his own party.

A senior US official said late Saturday that elements of the final G20 statement "are still being negotiated".

The official expressed hope the summit would commit "to end overseas financing of coal", offer "positive language" on decarbonising the power sector and see more countries sign up to targets on cutting methane. 

Speaking to the weekly Journal du Dimanche, French President Emmanuel Macron said the Rome summit had to "do its utmost" to ensure the success of Glasgow, but that "nothing is ever written before a COP". 

"Let's not forget that in Paris, in 2015, nothing was decided in advance," Macron said.