The UK has committed up to £720 million to an international fund to help developing nations adapt to climate change.
The Green Climate Fund will target poor countries in an effort to help them reduce greenhouse gas emissions.
The UK’s contribution takes the fund to around $9 billion (£5.7bn), which includes investments from the US, Japan, Germany and France.
Energy Secretary Ed Davey said: “The poorest and most vulnerable on the planet are already suffering the effects of climate change and it’s our moral duty to act.
“From protecting low-lying islands and coastal settlements from the impact of rising sea levels to helping farmers struggling with lower crop yields caused by the weather effects of climate change – British aid can save lives.”
The World Bank will manage the financial assets of the fund, which will start programming in 2015.