Competition for workspace could drive home-grown companies out of the city, an influential economist has warned on the eve of his retirement.

Despite a burgeoning economy and stellar job growth, the last office complex built in Brighton was completed nearly a decade ago.

Tony Mernagh, outgoing executive chairman of the Brighton and Hove Economic Partnership, warned that fierce competition for space would drive up rents and could force companies out.

Jubilee Street in the North Laine was the last significant development of 1,670 square metres, completed in 2007.

City View, next to Jury’s Inn by Brighton Station, is due to deliver more than 3,000 square metres later this year and Circus Street will deliver another 2,800.

Mr Mernagh said: “The City Plan identifies a need for 112,000 square metres over the next 20 years.

“Despite this, land has only been identified for 85% of that figure and the need is more pressing than a 20 year time frame would suggest.”

The city has around 270,000 square metres of office space in total but less than 6% is available to let and much of that is old 1960s and 1970s stock that is in dire need of refurbishment.

Only 3,000 square metres of Grade A stock is available.

Mr Mernagh added: “The benefit of refurbishment of older stock has been amply demonstrated in recent times with both Sovereign House in Church Street and One Gloucester Place being fully let after extensive refurbishment in 2012 and 2011 respectively.

“Rents for Grade A property are now hovering between £237/sq metre and £269/sq metre. Increasing demand and short supply can only push them in one direction.

“Competition for the City View development later this year is likely to be intense. It’s a great time for owners of clapped out workspace to invest in refurbishment.”

Philip Graves, director of Graves Jenkins, added: “For a number of years now, the city office supply has been strangled by the lack of new Grade A stock.

“The Brighton office market is probably at its peak now with a high volume of demand, which is naturally pushing rents up to record levels – in fact so much so, that developers can now justify building speculatively knowing that quality tenants are in the waiting.

“This has to be great news for the economic prospects for the city. I only wish we had more land on which to develop.”