Campaigners have called on the government to prioritise investment in the Green Belt in the forthcoming 25-year plan for the environment.
The Campaign to Protect Rural England says the land surrounding towns and cities is valuable in giving people access to the countryside and opportunities for recreation - but warns it is being 'nibbled away'.
It also argues that the woodland and wetland in Green Belts can help mitigate climate change.
CPRE planning campaign manager Paul Miner said: 'The Green Belt is successful and popular, preventing urban sprawl and giving people the opportunity of getting away from it all.
'With the increasing pressure of development it is more vital than ever, yet we are nibbling away at it month by month while the Government looks the other way.
'The Green Belt’s future depends on the Government’s desire to protect it and to fund opportunities to use that land for further public benefits.'