"In practice, the government's 'grey belt' policy has not been about building on petrol stations but an existential threat to the protections of the Green Belt"
- Roger Mortlock - CPRE
New research from CPRE, the countryside charity, reveals that the government's grey belt policy is paving the way for large-scale development on England's unspoilt rural landscapes, not on unused car parks and derelict petrol stations as ministers promised.
Since the policy was introduced in December 2024, 13 developments of ten or more homes have been approved by government planning inspectors on grey belt land in the Green Belt. The approvals have been granted over the heads of local councils.
Of the 1,250 homes these schemes will deliver, 88% will be built on previously undeveloped countryside. These developments make up more than 90% of homes granted planning permission on grey belt sites by inspectors. A further 21 smaller schemes, totalling no more than 91 homes, comprise the remainder.
When the policy was introduced in December 2024, the government gave disused petrol stations and abandoned car parks as examples of sites in the Green Belt that could be considered grey belt and released for development. In April 2024, Sir Keir Starmer described grey belt land as poor-quality scrubland, mothballed on the outskirts of town, as well as previously developed land such as disused petrol stations and car parks. "We'll prioritise ugly, disused grey belt land, and set tough new conditions for releasing that land," said Sir Keir Starmer.
However, a different reality has emerged in practice.
Approval has been granted, for example, for 57 houses on some of the country's best-quality farmland in Tonbridge, Kent. In Castle Point, Essex, 47 houses have been granted planning permission on a designated Local Wildlife Site. Both examples comprise Green Belt land now considered grey belt.
Earlier this year, other CPRE research demonstrated that there is enough previously developed land in England for 1.4 million new homes, of which almost half have already been granted planning permission. This shows that the government can move quickly towards its UK-wide target of 1.5 million new homes with limited development on unspoilt countryside. Targeting the Green Belt is a choice, not a necessity.
CPRE is calling on the government to amend its grey belt definition and ensure developments occur only on previously developed land. The charity also wants high-quality farmland and important wildlife habitats protected from development. Additionally, CPRE advocates for ambitious and legally binding targets for genuinely affordable and socially rented homes in all new developments, with developers held to account if they are not delivered.
In Tonbridge, Kent, a planning inspector allowed Dandara South East Ltd's appeal for 57 homes on the former Court Lane Nurseries in February 2025. The site sits within the Green Belt and near the Hadlow Conservation Area. Local objections highlighted increased traffic, pressure on local services and the loss of Grade 1 agricultural land. This decision erodes the protected Green Belt, fragments natural habitats and removes high-quality farmland. It sets a precedent for urban sprawl, undermining long-term environmental resilience and the integrity of rural landscapes.
In Benfleet, Castle Point, Essex, planning permission was granted in August 2025 for up to 47 homes on land east of Chase Mews, despite its designation as part of the Thundersley Plotlands Local Wildlife Site. The site's grassland and hedgerows act as a vital ecological corridor for bats, birds and badgers. Development will fragment habitats, reduce biodiversity and increase recreational pressure on nearby protected sites, even with mitigation measures. The loss of Green Belt space undermines local nature connectivity and contributes to urban sprawl, threatening long-term ecosystem resilience and species survival. This decision prioritises housing over environmental sustainability.
"In practice, the government's 'grey belt' policy has not been about building on petrol stations but an existential threat to the protections of the Green Belt," said Roger Mortlock, chief executive at CPRE.
"Our latest research shows that the policy is vague, subjective and misleading to the public," explained Mortlock. "Its lack of clarity has been good news for large housebuilders but bad news for everyone who loves the countryside."
"We know from CPRE branches across the country that the situation is getting worse, as local authorities are so desperate to meet revised housing targets that they are forced to approve speculative development in the Green Belt," noted Mortlock.
"The Green Belt is the countryside next door for almost 30 million people in this country," said Emma Marrington, policy lead at CPRE. "As well as having some of the country's best-quality farmland and most important wildlife habitats, these places around our largest towns and cities play a vital role in helping to deliver the government's target of 30% of land protected for nature by 2030."
"We've got to stand up for England's Green Belt," added Marrington. "Once it's lost, it's lost for good."
