Joan Ruddock, UK Minister for Biodiversity, was among the politicians who made the pledge to work towards zero net deforestation by 2020 - that means that global forest coverage must remain the same, taking into account deforestation and reforestation.
The pledges were made by signing a postcard addressed to WWF International's Director-General, James Leape.
Despite much effort, deforestation continues at an alarming rate - 13 million hectares per year, or 36 football fields a minute.
Deforestation and degradation of the world's forests have dramatic consequences for biodiversity, global climate and millions of people. About 1.6 billion people worldwide depend on forests for their livelihoods, with 60 million indigenous people depending on forests for their subsistence.
Forests contain 90% of the world's terrestrial biodiversity and have a vital role to play in the fight against global warming, being the largest storehouse of carbon on Earth.
Deforestation, particularly in the tropics, is the third largest source of greenhouse gas emissions, generating up to 20% of global carbon emissions.
"WWF would like to see the Convention on Biological Diversity adopt this 2020 zero net deforestation target here in Bonn," Leape said.
"Governments have to act now or we will lose even more of the forests that are life's basic building blocks, and that provide essential services to humanity," he explained
WWF believes that by signing the pledge governments have demonstrated their commitment to halting global forest loss. As the majority of deforestation takes place in developing countries, developed countries, such as the UK, must step up to provide support to help these countries achieve this target.