Qatari Diar cannot alter the facade of the Chancery building
The Grade II listed US embassy building in central London has been sold to Qatari Diar, the same real estate firm which owns the Chelsea Barracks site.
The Chancery building, in Grosvenor Square, was listed in October for its modernist concrete facade, which means the new owners cannot alter its design.
The embassy will operate from the Mayfair building until its new south London embassy building is completed.
The complex in Wandsworth is expected to be completed by 2016 or 2017.
Qatari Diar, the real estate investment arm of Qatar's government, was in the news after it withdrew Lord Rogers' modernist design for the 12.8 acre Chelsea Barracks site in west London in June after Prince Charles called the plan "unsympathetic".
The 600-room embassy, completed in 1957, is one of the early works of modernist architect Eero Saarinen and was given protected status by English Heritage.
The embassy plans to move to a 20-storey building at a five acre site in Nine Elms Lane in Wandsworth.
The US government will also announce the winner of a design competition for the new embassy in early 2010 and work at the site is expected to commence by 2012.