They're calling it Pleasure Island - a project which would revolutionise the face of Brighton and Hove and create a world-famous attraction.

The £500 million scheme would give the city a leading venue for conferences, with world leaders flying in by helicopter, as well as top leisure facilities.

At the core of the star-shaped island, situated two-thirds of a mile out to sea, is a huge glass dome under which there would be artificial 24-hour sunshine, guaranteeing visitors good weather throughout the year.

And the development could see the end of shingle beaches in the city, with sand introduced along the coast.

The island is approximately 21,000sqft and would look like a huge power station between the Palace and West piers. It would be lit up at night, resembling a giant liner permanently moored off the city.

A similar star-shaped island is already being constructed in Dubai.

First drawings of Pleasure Island include a 300ft high hotel complex, conference halls, leisure dome and eight smaller blocks of residential flats on each arm of the island with leisure facilities on the roofs of each block.

There would also be lines of shops and bars, as well as a heliport on top of the 50-storey hotel.

The conference centre would be linked to the luxury hotel and would make it an ideal venue for international conferences, as security would be easy to organise.

Visitors would get to and from the island by plane or a high-speed bullet ferry from a jetty on Brighton beach.

Once on the island, they could walk down a parade of shops with a range of restaurants and boutiques. There would be swimming and spa facilities.

The island would not need planning permission from the city council, whose jurisdiction ends at the beach.

At present, the project is only at the drawing board stage, but funding could be found by money from international pension funds, perhaps from Russian sources.

No application has been submitted to the city council, which would have to give permission for a landing stage or a small harbour to be constructed on Brighton beach.

Any planning application would have to be put to the Office of the Deputy Prime Minister and the Crown Commission, which has jurisdiction of the English Channel.

Details of the project have been released exclusively to The Argus by Alan Phillips, the architect behind the scheme.

The Brighton-based architect insists building out to sea is the only way forward for the city, where virtually all development space has been used up.

Mr Phillips has notified Brighton and Hove planners that he is working on the project, which will provoke debate about sea-based building.

A spokeswoman for the city council said: "We await the proposals with interest."

This island would be built on a huge concrete platform. All pebbles would be removed from beaches between Shoreham and Brighton to create a reef to protect the man-made structure.

Between the reef and the island there would be still water, ideal for swimming and boating.

Removal of the shingle between Brighton and Shoreham would soon ensure sand returned to the city's beaches.

Mr Phillips, of Alan Phillips Associates, is one of the city's leading architects, and has a reputation for innovative work.

He and his company have been involved in a number of projects, including the building of new homes in St Nicholas Road, Brighton, the building of a millionaire's futuristic mansion in The Droveway, Hove, and flats in Blazehill Road, Rottingdean.

He has also designed a new house for musician Bono of U2 in the South of France and written five books on architecture.

Mr Phillips caused a furore in the summer when he put forward plans for a tower block on Rottingdean seafront, which has been so far rejected by planners.

The 50-year-old, who lives on Hove seafront, is confident he will see the island built.

"The idea came when I was walking along the seafront at the height of summer and I saw a family with four young children. They looked miserable because it was not a particularly nice day and they did not know what to do.

"I thought there ought to be a large complex like a Centre Parcs where people could swim and spend their days irrespective of the weather.

"Brighton needs a top-class leisure complex and world-class conference facilities. If the city is to remain a top leisure and conference centre and one of the boldest cities in the world then we will have to build out to sea.

"I have spent all my life in Sussex and I want to see Brighton and Hove retain and improve its reputation as a world-class resort and conference centre. The way forward is building into the sea."

Brighton and Hove estate agent Glenn Mishon, of Mishon Mackay, said: "This sounds like a very interesting project.

"I am sure there are many people who would love to live and work on an island off Brighton."