A report released on Friday by the Organisation for Economic Co-operation and Development said that rich countries likely missed a goal to contribute $100 billion last year to helping developing nations deal with climate change after increasing funding by less than 2 per cent in 2019.
In messaged comments from his climate round-table speech on Monday, Italian prime minister Mario Draghi said the $100 billion pledge had to be fulfilled.
He also said current measures on curbing global greenhouse gas emissions were insufficient.
"All this is clear: this is far from the trajectory needed to reach net zero by 2050," he said.
A UN analysis of country pledges under the Paris climate agreement released last week said that under current national pledges, global emissions would be 16 per cent higher in 2030 than they were in 2010 - far off the 45 per cent reduction by 2030 that scientists say is needed to stave off disastrous climate change.
Without more ambitious commitments, global temperatures could hit 2.7 degree Celsius above pre-industrial levels by the end of the century, the UN said.