British Land has let 6,500 square feet at 10 Portman Square in London to investment management company Independent Franchise Partners. The building, which was completed last year, is now just over 75% let. It forms part of the company's 2010 development programme, which is now 78% let or under offer. Head of office leasing at British Land James Danby said: "Demand for office space at 10 Portman Square has been very strong since we launched the building a year ago, owing to the exceptional design and its location, just a stone's throw from Mayfair. "We are naturally very pleased to have let space to Independent Franchise Partners and we look forward to welcoming them to the building."Shares had slipped 0.28% to 701p by 08:38.NR