NB Real Estate, the surveying group formerly known as Nelson Bakewell, said that empty office space in the City had soared by 46% in a year. At the same time, rents on the best City offices have fallen by 11.5% from £65 per sq ft to £57.50.

The research for the third quarter of 2008 showed there was 7.8m sq ft of office space lying empty in the City, compared with 5.4m sq ft last year.

A separate report by commercial property adviser Atisreal warns of rising vacancy rates across London for the next 12 to 18 months.

The Times, Daily Telegraph