G20 leaders gather for a second day of their Rome summit on Sunday, with all eyes on whether they can deliver a meaningful commitment on climate change ahead of crucial 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.
However, some activists expressed hope that in the final hours of wrangling, some progress would be made before nearly 200 leaders, including many of those in Rome, fly to Scotland.
US President Joe Biden is among those pushing for action in Rome, although his own ambitious climate policy is mired by infighting among his own party.
A senior US official said elements of the final G20 statement "are still being negotiated", adding that the Rome summit was about "helping build momentum" before Glasgow.
The official expressed hope that 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 that 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," he said.
President Xi Jinping of China — by far the world's biggest carbon polluter — is absent from the meeting, as is Russia's Vladimir Putin, although they sent representatives and are logging in via videolink.
Britain's Prince Charles, a long-time environmentalist, will be making his case for change on Sunday as a special guest of the summit, speaking ahead of final working sessions.
Going alone 'not an option'
On Saturday, summit host Mario Draghi, the Italian prime minister, urged G20 leaders to act together on climate, but also on improving the delivery of vaccines and on helping the world recover from the devastation of Covid-19.
"From the pandemic to climate change, to fair and equitable taxation, going it alone is simply not an option," he told the gathered leaders.
The G20 showed on Saturday they could work together on some issues, green-lighting a deal for a minimum tax of 15 percent on global corporations, as part of a reform plan inked by almost 140 nations.
US Treasury Secretary Janet Yellen hailed it as "historic", while German Chancellor Angela Merkel — attending her last G20 summit with her likely successor Olaf Scholz — called it a "great success".
Rome hosted the first in-person G20 summit since the coronavirus pandemic, and chose to do it in the monumental surroundings of EUR, a fascist-era neighbourhood known for its modernist architecture.
The gathering gave leaders the chance for sideline meetings, including several involving Biden.
He mended fences with France's Emmanuel Macron after a recent row over a submarine deal, and the pair met with their British and German counterparts to express "grave and growing concern" over Iran's nuclear activities.
On Sunday, the US president's agenda includes bilateral talks with Turkish President Recep Tayyip Erdogan covering Syria, Libya and defence deals.
Earlier this month the Turkish leader threatened to expel ambassadors from the United States and nine other Western nations over their support for a jailed Turkish civil society leader.