A new $280m (€208m) initiative to help save the world's remaining forests was launched by the UK, the US and Norway at the United Nations climate change talks in Warsaw on Wednesday.

The money is aimed at encouraging the sustainable use of land, including ensuring that fewer forests are lost to agriculture – the biggest cause of deforestation – and that there is a market for sustainably produced forestry goods, including food, fibre and timber.

Norway is earmarking up to $135m, the UK $120 million and the US $25m for the first year.

But the contributors to the fund acknowledged that the money was not new, as it came from existing climate aid budgets. The plan, called BioCarbon Fund Initiative for Sustainable Forest Landscapes, is aimed at kickstarting the Redd+ scheme, for the reduction of emissions from deforestation and forest degradation, which has been in the works for more than six years but is still not fully operational. The World Bank will be involved in its implementation.

Ed Davey, the UK energy and climate change secretary, told the conference: "Our global forests are the lungs of the world, and protecting them is fundamental for our survival. When we hand these forests to future generations, we must be able to say we exercised our stewardship wisely and responsibly. This century, tree-cover the size of Greenland has been destroyed by logging, fire, disease and storms. We have the opportunity now to pull forests back from the brink – reducing emissions and safeguarding the wildlife, agriculture and other livelihoods that depend on the forests. We must not let that opportunity pass us by."

John Kerry, US secretary of state, speaking by video link, said: [This is a] critical new tool to help us meet our responsibilities to future generations. It will help countries make progress on sustainable land use practices. The United States stands with willing partners in the fight against global climate change and I look forward to continuing our work together to ensure a more secure future, not only forested countries but for the entire planet that we share."

Davey said that one new aspect of the initiative was that it would work with the private sector to promote the sustainable use of forest products.