Leaders of the Group of 20 major economies agreed on a final statement on October 31 that urged "meaningful and effective" action to limit global warming, but angering climate activists by offering few concrete commitments.
The result of days of tough negotiation among diplomats leaves huge work to be done at the broader United Nations COP26 climate summit in Scotland, which starts this week.
U.S. President Joe Biden said he was disappointed that more could not have been done and blamed China and Russia for not bringing proposals to the table.
"The disappointment relates to the fact that Russia and … China basically didn’t show up in terms of any commitments to deal with climate change," Biden told reporters on October 31 after the two-day meeting in Rome.
Although the G20 pledged to stop financing coal power overseas, they set no timetable for phasing it out at home, and watered down the wording on a promise to reduce emissions of methane -- another potent greenhouse gas.
However, Italian Prime Minister Mario Draghi, who chaired the Rome gathering, hailed the final accord, saying that for the first time all G20 states had agreed on the importance of capping global warming at the 1.5 degrees Celsius level that scientists say is vital to avoid disaster.
"We made sure that our dreams are not only alive but they are progressing," Draghi told a closing news conference, brushing off criticism from environmentalists that the G20 had not gone nearly far enough to resolve the crisis.
The G20, which includes Brazil, China, India, Germany and the United States, accounts for 60 percent of the world's population and an estimated 80 percent of global greenhouse gas emissions.