Qatar's sovereign wealth fund Qatar Investment Authority (QIA) said it had completed the acquisition of Credit Suisse's headquarters in London and leased it back to the bank.

The 546,114 square-feet building at One Cabot Square in Canary Wharf was leased to the bank under a long-term agreement that runs until 2034, Qatar Holding, the foreign investment arm of QIA said in a statement on its website on Monday.

The value of the deal was not disclosed.

The authority was to pay 330 million pounds ($517 million) for the property, with a separate leaseback agreement to be put in place with the Swiss lender, two sources told Reuters last month.

QIA holds a 6 per cent stake in Credit Suisse and owns shares in Songbird, the majority owner of Canary Wharf Group.

Gulf-government backed funds have been on a buying spree in Europe and are eyeing investments in real estate, infrastructure and other sectors.

Qatari Diar, a property arm of the fund, along with Canary Wharf, won a 300-million-pound deal to redevelop the Shell Centre in London that houses the Royal Dutch Shell's London headquarters in July.

Qatar has other high-profile investments in London, including the US embassy in Grosvenor Square and Harrods department store.-Reuters