The Council for the Protection of Rural England says West Sussex is a test case for the argument that rural counties cannot support more houses.
The county has little 'brown land' for housing, Today reported.
But David Coates of the House Builders Federation said: 'We look to planning authorities ... to produce imaginative solutions rather than just saying that West Sussex is full or Surrey is full. They're clearly not.'
'West Sussex is taking its fair share... I sometimes wonder why we assume these numbers have got to be matched,' he told the programme.