More than 100 world leaders have signed a pledge to reverse deforestation in one of the first major agreements of the Cop26 summit in Glasgow.
The UK, US and UAE were among the countries collectively responsible for more than 85 per cent of the world's forests, who put their names to the plan.
The pledge is to use $19 billion ($25.9 billion) in public and private finance to restore degraded land, tackle bushfires, protect indigenous people and focus on key areas such as the Congo Basin.
UK Prime Minister Boris Johnson described it as a "landmark commitment" and welcomed that fact that Brazil, which has courted controversy with its stewardship of the Amazon rainforest, was among the signatories.
He said it would support the Cop26 goal of restricting global warming to 1.5ºC above pre-industrial levels through the absorption of carbon emissions by forests.
"We have to stop the devastating loss of our forests, these great, teeming ecosystems, trillion-pillared cathedrals of nature," Mr Johnson told Cop26 delegates on Tuesday.
"With today’s unprecedented pledges, we will have a chance to end humanity’s long history as nature’s conqueror and instead become its custodian.”
US President Joe Biden said Washington would lead the way with a $9 billion plan to restore millions of hectares of American forests.
"Conserving our forests and other critical ecosystems is an indispensable piece of keeping our climate goals within reach," he said.
"We need to approach this issue with the same seriousness of purpose as decarbonising our economies."
The Glasgow Leaders' Declaration on Forest and Land Use will cover more than 33.6 million square kilometres, a statement from Mr Johnson's office said. It aims to reverse forest loss and degradation by 2030.