Eco-towns will fail because businesses and residents will make the same locational choices as elsewhere, urban policy expert Alan Wenban-Smith warned in London on Monday.

‘Co-location of new jobs and houses is ineffective in reducing travel demand or car dependency, because it does not change the propensity to travel,’ he said.

‘Travel grows not because of need, but because of demand.’ Between 1972 and 2006, while trips per head rose by 8%, total travel in person/km soared by 74%.

‘People are making longer trips, and new development doesn’t explain this. Improving transport links will not cure congestion and co-location makes no difference, he said.’

He also attacked Communities and Local Government planning and housing policies for focusing on new development, while 90% of locational choices are from ‘churn’ of existing stock.