Business leaders have written to every member of Brighton and Hove City Council urging them to build 700 homes at Toads Hole Valley.
Brighton and Hove Economic Partnership sent the letter after the publication of the City Plan which has been produced by the council but has not yet been approved.
The City Plan spells out broadly what can be built and where between now and 2030.
The Economic Partnership said that building at Toads Hole Valley was the most controversial proposal in the plan.
Opponents to the plan, including Labour councillor Brian Fitch, said that Toads Hole Valley was a vital green space on the edge of the South Downs.
Councillor Fitch has urged colleagues to focus instead on brownfield sites such as Shoreham Harbour to ensure that enough new homes are built for the growing population of Brighton and Hove.
Those in favour of building at Toads Hole Valley have said that it was cut off by the A27 Brighton Bypass from the Downs. It is outside the new national park.
Gary Peters, the chairman of the Economic Partnership, and executive director Tony Mernagh wrote jointly to councillors.
Their letter on behalf of the Economic Parnership said: “Dear Councillor, The Economic Partnership is urging all councillors in the local authority to support the City Plan and especially the development of Toads Hole Valley which will be discussed at the Policy and Resources Committee on 24 January and full council at the end of the month.
“Hardly a month goes by when those involved in the city’s economy don’t thank Councillor Geoffrey Theobald’s late father for his foresight in delivering the Brighton Centre in the 1970s thus transforming the city’s fortunes.
“Over the past 35 years it has generated billions of pounds, supported tens of thousands of jobs and driven a large chunk of the economy and, despite its age, it is still pulling in the crowds.
“The development of Toads Hole Valley presents another opportunity for a vision equal to the Brighton Centre that will be similarly valued not just by generations to come but also today’s young, growing population starved of jobs and homes.
“The vision of a truly sustainable community of 700 desperately needed houses and a new school and employment space, creating 1,500 new jobs during its construction with training and apprentice opportunities, is on a par with the visions of the great aldermen of the city’s past: Carden, Theobald, Cohen, etc.
“The wholesale realignment of King George VI Avenue to the other side of the valley parallel with the A27, immeasurably improving the lives of the residents living on its fringes, is icing on the cake.
“As you are all aware, the City Plan will not be accepted by government unless the housing numbers destined for the valley are included.
“I am confident that our politicians do not want to embarrass the city by seeing the plan rejected or incur the public expense of resubmitting it which would also hold many major developments hostage to the delay.
“In politics there are inevitably party political considerations to take into account during decision-making but this is a time to put them aside.
“The Economic Partnership urges all politicians to vote in favour of the plan and the development of Toads Hole Valley.
“This and future generations will thank you for it for generations to come.”
