British Land is set to sell Plantation Place, its flagship office development in the City of London to Insight, the fund management division of HBOS (at tie of going to press), for an estimated £525 million in the UK’s biggest single-asset commercial property deal.

British Land acquired the site for £15 million in 1971 and redeveloped it for a scheme completed in 2004.

If the deal goes ahead, it will top the £520m Tishman Speyer paid for CityPoint, a 36-storey tower in the City.