Leaders at the G20 have agreed on carbon neutrality “by or around mid-century” as the conference came to a close just ahead of the UN’s Cop26 summit.
Politicians attending the event in Rome also pledged to end public financing for coal-fired power generation abroad.
But they set no target for phasing out domestic coal.
Their agreements came on the eve of Cop26 in Glasgow, which Boris Johnson has described as a “moment of truth” for humanity.
Crunch climate change talks are due to begin in the Scottish city on Monday.
Mr Johnson spent the weekend pushing the message that the developed countries needed to move further and faster in order to succeed in meeting the goal set out in the Paris climate accords of limiting global temperature rises to 1.5C.
“Cop26 will be the world’s moment of truth. The question everyone is asking is whether we seize this moment or let it slip away,” he said.
“I hope world leaders will hear them and come to Glasgow ready to answer them with decisive action.
“Together, we can mark the beginning of the end of climate change – and end the uncertainty once and for all.”
According to the final communique from the summit, the G20 reaffirmed past commitments by rich countries to provide 100 billion US dollars annually to help poorer countries cope with climate change.
Leaders agreed to “put an end to the provision of international public finance for new unabated coal power generation abroad by the end of 2021”.
G20 leaders said they will “accelerate our actions across mitigation, adaptation and finance, acknowledging the key relevance of achieving global net zero greenhouse gas emissions or carbon neutrality by or around mid-century”.
