Its residents would have the best sea views on the South Coast.

Several hundred feet high, a giant tower over Brighton Marina would include about 1,000 new homes.

Built in a wave formation to reflect the sea below, the scheme by Brunswick Developments would cost £175 million. Forty per cent of the homes would be low-cost.

Managing director Andrew Goodall said: "We are working on a tower of about 30 to 40 storeys.

"It is likely to end up looking like two slender towers, the balconies being integral to the building, so they can be used as a conservatory or, in fine weather, the doors can be opened up and used as a balcony."

The skyscraper has been designed by Jim Eyre, a partner in the international firm of architects Wilkinson Eyre, whose most famous structure is the "winking eye" bridge in Newcastle-upon-Tyne.

Brunswick is already talking to a leading firm of housebuilders about the private sector development.

It also proposes a partnership with the Guinness Trust, which has undertaken work in Brighton, about 400 low-cost homes for key workers to comply with the policy of Brighton and Hove City Council. It would be one of the largest social housing schemes in the city.

The site is the beach south of the David Lloyd Centre and the casino at the harbour.

Some land would have to be reclaimed for the development or it could be built partially over the water.

Since the marina was conceived in the Sixties, there has been a general rule that no building should exceed the height of the cliffs.

But Brighton and Hove now has a tall buildings policy and Deputy Prime Minister John Prescott is urging the council to accept schemes of higher density than in the past.

The 1,000 homes would make a substantial dent in the number planned by Mr Prescott to meet the shortage in the South-East.

Mr Goodall said: "The marina needs a landmark and this building will provide it. This is a wonderful site and we are making something of it.

"This is a deliverable scheme, it can be built. We are also committed to the rapid transport system."

The council has approved the idea of a transport system to link the main developments along the seafront. The current favourite is a guided bus system as this is comparativbely cheap and easy to build.

Mr Eyre pointed out the site was more than 400 metres from the cliffs, unlike most existing housing at the marina.

He said: "It will be a landmark at one of the entrances to Brighton and Hove."

He said it should not affect the Grade I listed buildings of Lewes Crescent and Sussex Square, which look straight down to the sea rather than to the east and the tall and slender tower would not overshadow existing homes in the harbour or Marina Gate on the cliff top.

The tower would be surrounded by a cluster of smaller buildings of ten, 12 and 14 storeys to form a cohesive development.

There would also be a new yacht club, space for the RNLI and marina offices plus five or ten more bars and restaurants and a new piazza.

The scheme would be as far as possible sustainable.

Environmental experts Connell Mott Macdonald are being employed to ensure this.

Mr Goodall said: "We will be building energy efficiency and proper waste management into the design of the buildings."

The rapid transport system could have its eastern terminus in the development.

Instead of winding its way out of the harbour along the existing road, the system would take a higher level route nearer the beach to head west. Pedestrian and cycle routes would also go this way from the harbour.

There would be few parking spaces so residents would be encouraged to use the rapid transport system.

Another feature planned by Mr Eyre is a bridge linking the main harbour wall to the new development. It would be open most of the time to allow access by yachts but closed once or twice an hour to allow pedestrians to complete a circuit of the marina.

The bridge itself would be an architectural feature.

Mr Goodall believes the development would give form and substance to the marina, which has been built in a variety of different styles over the last 30 years.

The completed commercial areas would create 200 to 300 full-time jobs.

He said: "During the six to eight-year construction period, we estimate there will be approximately 200 full-time jobs. We will also look to have training programmes for construction workers.

"The advantage of a long build period is the ability to get training schemes up and running."

A planning application will be submitted to the city council later this year after widespread consultation.

It is likely more homes will be built at a later stage on another part of the site and talks are taking place with Asda about making better use of its land.

Up to another 600 homes could be provided and the store could be resited. Architect Auketts has been appointed by both partners.

A web site giving details will be available at www.BrightonMarinaFuture.co.uk