Plans were unveiled today for a science park on one of the largest open spaces in Brighton and Hove which could create up to 2,000 jobs.

The owners of Toads Hole Valley also intend to turn the rest of the site into a 60-acre public park under the controversial proposals.

The valley, which is bounded by King George VI Avenue, the Brighton bypass and the Hangleton estate, has been at the centre of debate over its future for years.

But today's news is the first time concrete proposals have been put forward.

No planning application has yet been submitted by the Cook family, owners of the valley for many years.

But surveyors Stiles Harold Williams and architects Lyons Sleeman Hoare have submitted a brochure to councillors showing what could be done.

Earlier this month, leading councillors approved a draft Local Plan which made no mention of the valley as a possible site for employment. The family hopes to change the Local Plan after consultation so it is included.

Robert Stiles said: "The development of Toads Hole Valley is often talked about in general terms without, perhaps, due consideration of exactly what it might involve."

He added: "We hope the brochure shows the land could be developed in sympathy with environmental considerations while at the same time providing considerable benefits for both the local residents and the town."

The brochure says a modern science and office/research park would have attractive, well-designed low-rise buildings with plenty of space around them.

Because of the slope of the land, the buildings in the centre of the site and close to the bypass would not disturb views.

This development, taking up a third of the valley, would help finance a public park open to all.

The land would be offered free to Brighton and Hove Council together with cash to turn it into the largest park in Hove.

The brochure says: "The valley could provide 60 acres of new public parkland and 2,000 new jobs.

"It will give local companies the chance to expand as opposed to having to move away from the town. The valley can give Brighton and Hove the opportunity to attract leading employers offering highly-paid jobs."

The brochure says there is a need for pleasant sites for businesses in Brighton and Hove with easy access to main roads. It adds: "Toads Hole Valley can provide the site and help to meet this need for offices. It can help attract international companies to South East England and remove the necessity for assisted area status in the town."

But local Tory councillor Vanessa Brown said: "We managed to get this site removed from the Local Plan and they are trying to get it back. I am very sorry this has come up again. We hoped we had removed the possibility of its returning."

Coun Brown, who chairs the Goldstone Valley Residents' Association, said: "Members will be very upset. They would like to see it left as an open space.

"They don't want it developed as a science park and they do not want to see it in the Local Plan."

The valley is currently unused. There were plans in the Nineties for it to be used as a stadium for Brighton and Hove Albion.