'Build on the boring areas of green belt'

Natural England - charged by ministers with overseeing England's conservation - said the 50-year-old zone around the outskirts of London should be broken up.

In a radical set of proposals the organisation says the best parts of the green belt should be safeguarded. But areas of less environmental importance should be considered for building "eco homes" and other green developments.

The plans prompted fury from environmental campaigners who warned that they would lead to concreting of the countryside around London.

A policy paper to be discussed today by the board of Natural England says there should be a "network" of green spaces rather than a blanket designated area.

"We have to consider the option of permitting development on the green belt in order to minimise impacts on the natural environment elsewhere," it says. "None of the current options for development are impact free.

"Of course, some green belt land will not be suitable for development. This includes environmental designations, flood plains and strategic gaps to maintain separation of settlements.

"These areas could be the basis of a new, less extensive green belt. Its form would probably be one of green gaps, green wedges and buffers rather than continuous belts."

Natural England was created last year through the merger of English Nature and the Countryside Agency. It was set up to "conserve and enhance the natural environment" on behalf of the Government. Andrew Wood, Natural England's director of policy, said "large pieces" of the green belt were " comparatively boring".

"The trees are there but they are not high quality in conservation terms and the environment is not great," he said. "What we are saying is let's make the green belt 'green'."

Mr Wood said Natural England was not suggesting the belt should be abolished, but it should be considered as "part of a range of options" when looking at development.

If the policy paper is agreed by the Natural England board, it will then be passed to ministers at the Department for the Environment, Food and Rural Affairs and the Department for Communities and Local Government.

Although ministers have promised in the past to protect the green belt, the Government's own housing targets have put intense pressure on local authorities to free land for development.

Ministers want three million new homes by 2020, of which two million may have to be built on new land.

The Campaign for the Protection of Rural England warned that altering green belt policy could "unleash an American-style swathe of car-dependent rule that could change England for the worse".

A spokesman said: "We don't believe there's much evidence to support a review of green belt policy and there's no evidence that it's not working."

A spokesman for the Department for Communities said: "Our position at the moment is that we are not planning any changes to the robust rules which protect the green belt."