A person familiar with the situation said the company would stop leasing the small mews property which, despite its location in Farm Street in the upscale district of Mayfair, is one of the more low-key headquarters for a FTSE 100 company.

Staff from the head office, who cover areas such as legal and finance, will move into Sea Containers, a large office on the south bank of the River Thames that is already home to some of WPP's agencies.

That building may not be large enough for all the staff in the parent company however and the long-term ambition is for all staff to work together, the person said, indicating that that may be temporary.

The move, taken by joint chief operating officers Mark Read and Andrew Scott, marks a fresh start for the group after Sorrell took on Farm Street and its warren of corridors and low ceiling offices in 1987 as part of his acquisition of JWT.

Sorrell, one of Britain's most high-profile businessmen, quit the group in April after it said it had investigated an allegation of personal misconduct made against him.

Sorrell denied subsequent reports he had visited a prostitute and paid using company money when asked about his exit from WPP at the Cannes Lions advertising festival in June.

The company is expecting to announce a new chief executive in early September, with Read seen as the leading candidate. Advertising title Campaign was the first to report the news. A spokesman for WPP declined to comment.

(Reporting by Kate Holton, Editing by William Maclean)