Private equity company Blackstone Group has expanded its property presence in London, buying the 12-building Devonshire Square office and retail complex from rival Rockpoint and the Abu Dhabi Investment Authority (ADIA), according to a source familiar with the deal.

The deal was signed on Friday for just under 340 million pounds ($549 million), according to the Financial Times, about 17 percent below the 410 million pounds paid by Rockpoint and ADIA for the five-acre Devonshire Square site in 2006 during a peak in the London office-property market.

Rockpoint and ADIA redeveloped the Devonshire Square site. The project is near Broadgate, the office complex in the City of London in the heart of the financial district, that Blackstone owns in a 50-50 joint venture with British Land.

Blackstone last week signed a S$215 million ($173 million) deal to make its first acquisition in Singapore, buying the StarHub Green project from Germany's SEB Asset Management .

It has raised more than $10 billion towards Blackstone Real Estate Partners VII, a global property fund. The purchase is a co-investment between that fund and the company's third European fund, the source said.

Blackstone declined to comment, and Rockpoint could not immediately be reached for comment.

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