Its Climate finance from developed to developing countries report looked at public finance flows in the 2013-17 period.

Since 2013, when public climate financing was $39.5bn, there has been a 44% increase.

The data includes bilateral public climate-related aid from developed countries, multilateral climate finance and officially climate-related export credits from developed countries.

The 2017 figure is in line with previous OECD estimates, which forecast public climate finance to reach $66.8bn in 2020.

According to the report, bilateral public climate financing – money from one country to another – rose by 20% between 2013 and 2017. Multilateral climate financing rose by 79% to $27.5bn last year.

Within this, finance for adaptation to climate change rose by 65% from $7.8bn in 2013 to $12.9bn in 2017.

Money for mitigation activities, for example projects to cut emissions, rose by less – 38% – but mitigation accounts for most of the funding at $38.9bn.

The report said: “All regions received increasing amounts of public climate finance over the period.

“Asia, followed by Africa and Latin America, received the largest share of bilateral and multilateral climate finance over the period at more than 80% in any given year.”

Grants represented over a third of bilateral and less than 10% of multilateral climate financing.

Loans accounted for 60% of bilateral and nearly 90% of multilateral finance.