Details of the first phase of a massive and controversial government house building scheme in the south east of England are to be announced on Wednesday.

Deputy Prime Minister John Prescott will name the first sites to be developed under plans to build 200,000 homes to tackle a chronic shortage of affordable housing.

The five strategic sites lie in the Thames Gateway area of east and south-east London, Essex and Kent. The plans have been criticised by environmental campaigners, who are worried about the fate of the green belt. Others have raise concerns over poorer air quality, worse traffic and overcrowding in schools and hospitals.

These are long-term decisions. This is about how you make it happen Deputy Prime Minister John Prescott. The package of new house building was first announced by John Prescott in February.

Four key areas were highlighted then as areas for future development. These included the London-Cambridge M11 corridor, Milton Keynes, Thames Gateway and Ashford in Kent.

At the time Mr Prescott said the four "growth" areas, together with London, had the potential to deliver 300,000 more jobs and the extra homes over the next 15-20 years.

Speaking on BBC Radio 4's Today programme on Wednesday, he defended the building of more homes in the south east and called the Thames Gateway "the greatest area for development".