Nearly half the homes at Ford's ecotown will be affordable

She told the BBC they would help to tackle climate change as well as provide affordable housing. Between 30-50 per cent of the 5,000 new properties in a Ford eco-town, if it is built, will be affordable.

Every home within it will be designed to meet low energy and carbon neutral targets in what will be the first new towns since the 1960s.

Ms Flint said: "We have a housing shortage in this country and that's why we need to build more homes.

"But we also need to think about sustainable homes in sustainable communities."

The government plans to form a panel of experts to test the potential developers to ensure they meet tough standards before they are given the right to build the developments.

"Bidders will have to meet the highest standards for sustainability, affordability and creativity," she stated.

Ecotowns will also need to boast a secondary school, medium scale retail centre, good quality business space and leisure facilities.

The government has stressed that any new towns proposed will have to go through the usual planning process. Local people and councils will have the right to challenge the plans. As well as environmental standards, the developers will have to show they can deliver their scheme with funding and management controls in place and that the proposals are affordable.

Last Thursday'sannouncement began the first of four stages in the planning process for the ecotowns. The current phase is a three month long consultation. This will be followed by more consultation this summer on a sustainability appraisal, with a more detailed assessment of the locations.

Later this year will come a government decision on the ten sites chosen for an ecotown.