Countryside campaigners have challenged suggestions there is a shortage of brownfield land for new housing, claiming previously developed sites could be reused to build 1.5 million homes.
In the latest sortie in the debate over the Government's proposals to reform the planning system, the Campaign to Protect Rural England (CPRE) released a report which said there was sufficient brownfield land suitable for 1,494,070 homes.
The CPRE said the figure for England was equivalent to around six years' supply of housing at the rates the Government says new homes have to be built, or a 10-year supply if building continues at 2009 rates.
Supply of brownfield sites outstrips demand, the report suggests, with only three out of every five suitable plots being used for housing between 2000 and 2009. Even in the South East, where demand is highest, a quarter of suitable brownfield sites went unused, said the CPRE.
A number of organisations including CPRE want to see the "brownfield first" requirement, introduced in 1995 to boost the regeneration of previously-used urban sites before building on green areas, put back into the proposed planning policy.
The brownfield first policy has been replaced in the proposed new planning framework, which slims down more than 1,000 pages of policy to just 52 in a bid to boost growth, with a requirement to focus on "land with the least environmental or amenity value".
However, critics of the reforms fear they will pave the way for urban sprawl and building in the countryside, while neglecting the possibility of regeneration in towns and cities.
Those who oppose the brownfield first policy being reintroduced into the document include the Home Builders Federation (HBF), who say it has led to "garden grabbing", "urban cramming" and makes no distinction between derelict and environmentally-valuable land.
It will worsen the country's housing crisis and prevent economic growth and local decision-making, the HBF has warned.
A Department for Communities and Local Government spokesman said: "The draft policy would require that councils' plans should allocate land with the least environmental value. That means brownfield sites would be prioritised for regeneration except - as in the case of urban nature reserves - where they have become ecologically valuable."