'Grey belt' policy puts London's Green Belt farmland at risk, report warns

A planning loophole is opening up swathes of London’s countryside and farmland to development, a new report warns.

Despite Labour’s pledge to “preserve the Green Belt” and not alter its “purpose or general extent”, the report suggests large areas of protected land are now being opened up under the government’s ‘grey belt’ policy.

Published by the London Green Belt Council and CPRE Hertfordshire, it indicates the reality goes far beyond earlier assurances that development would be limited to previously used sites such as disused car parks or derelict petrol stations.

In Hertfordshire, 89% of last year’s 35 planning applications on Green Belt land were submitted under the ‘grey belt’ classification, highlighting the scale of change.

Across the wider London Green Belt, more than 80% of planning appeals between February and December 2024 were approved on ‘grey belt’ grounds, more than double the typical success rate.

The report argues that, in practice, no part of the Green Belt is off-limits.

Developers are already moving quickly to exploit the policy, while councils are being forced to reclassify previously protected land as ‘grey belt’.

A KC said the shift amounts to a “seismic reversal” of planning policy, adding it is now “virtually impossible” to challenge such applications, affecting “hundreds and hundreds of sites across the country”.

The report also raises concerns over how ‘grey belt’ is defined, with criteria described as so broad they allow development with “little or no restriction”.

Much of the land being released is said to be good-quality countryside, productive farmland and agricultural land, rather than previously developed sites.

Campaigners warn the policy could have significant implications for farmers and land use around London.

The report concludes the government increasingly views the Green Belt as having limited economic value unless it is built on, and warns that, if left unchecked, no area will be safe from development.

However, the government has argued planning reforms are needed to boost housing supply.

Campaigners also question whether releasing Green Belt land is necessary, pointing to more than 1.4 million homes granted planning permission since 2017 that have yet to be built. A similar number, the report suggests, could be delivered on brownfield land.

Public opinion remains firmly in favour of protecting the countryside.

A poll commissioned by CPRE found 86% of people consider Green Belt protections important, alongside strong backing for prioritising brownfield development.