A British real-estate consortium said Monday it agreed to buy the 42-storey tower that is Citigroup Inc.'s London headquarters for about 1 billion pounds (US$2 billion; ¤1.5 billion) in the second-biggest property transaction ever in Britain. The consortium includes Derek Quinlan, the founder of private equity and real estate group Quinlan Private, and Propinvest, a property investment company, the Associated Press reported. Located in the capital's Canary Wharf district, the building comprises more than 1.2 million square feet (366 million square meters) of space, all of which is leased by Citigroup, the world's largest bank. «This is a long-term personal investment in a prime property in the heart of London's new financial center,» Quinlan. In April, Europe's biggest bank HSBC Holdings PLC said it had sold its global headquarters in Canary Wharf to Metrovacesa SA of Spain for 1.09 billion pounds (US$2.18 billion) in the biggest single property deal in British history. HSBC will remain in the building under a 20-year lease, with a five-year option. That followed the announcement in February by Swiss Reinsurance Co. that it was selling its London headquarters, the 40-storey glass skyscraper known as «The Gherkin,» for 600 million pounds (US$1.18 billion) to real-estate corporation IVG Immobilien AG.