The gateway is a 40-mile-wide area from London to Kent and Essex

The government strategy paper has angered house builders who fear it will lead to fewer homes being built.

The Thames Gateway area, covering east and south-east London, and parts of Kent and Essex, is set for 120,000 new homes by 2016.

Housing minister Yvette Cooper denied there was a U-turn on the development.

It's about making the most of a wonderful gateway environment with beautiful green spaces and the river running through it Yvette Cooper, housing minister

The new Thames Gateway development, which spans 40 miles, aims to attract people on a range of incomes to create mixed communities.

It was announced by Deputy Prime Minister John Prescott three years ago as a way of attempting to meet the south's long-term housing needs.

The 300-page report leaked to the BBC is currently a discussion document, but it outlines major changes to the development strategy in the area and raises the possibility of a Thames Estuary Park.

Under the government's long term vision for the Thames Gateway, it would be comprised of an environmental "network" rather than a single green space.

'Jobs and regeneration'

Housing developments would have to take advantage of the latest eco-technology and be designed to the highest industry standards.

The report also emphasises the importance of open green spaces and landscape, and describes Ingress Park, on the bank of the River Thames in Greenhithe, as a role model housing development.

Steve Jones, managing director of Crest Nicholson, the company which built Ingress Park, welcomed the concept of an estuary park, but said it should have come sooner.

"It provides a framework for developers to be able to approach development within the Thames Gateway," he told the BBC.

The area is earmarked for 120,000 new homes and 180,000 new jobs

However, the Campaign to Protect Rural England (CPRE) believes the plans do not go far enough to protect green spaces.

Director Nigel Kersey said: "They've explicitly rejected the national park designation as such because they feel that it might restrict development.

"That could be a worrying sign that they intend to allow the landscape of the Thames Gateway to be covered in sprawling housing developments."

The housing minister said the report was all about taking forward Mr Prescott's plans for the Thames Gateway.

"It's about conservation. It's about making the most of a wonderful gateway environment with beautiful green spaces and the river running through it.

"We need new homes in the Gateway, we need new jobs in the Gateway, but we also want to make the most of the local environment as well," she said.

Ms Cooper added that the government was not scaling back on its original proposals for the area.