The Al Gurg family of Dubai is to buy the 20-storey office block at 240 Blackfriars Road at a price of £266.5 million.
240 Blackfriars Road is a 20 storey office building occupied by tenants including UBM, Boodle Hatfield, Ramboll UK and Lonely Planet.
The sale includes the adjacent residential building Cubitt House.
The three retail units are occupied by Abokado, Pret a Manger and The Coffeeworks Project.
The scheme was developed by Great Portland Estates and is currently owned by the Great Ropemaker Partnership, GPE's joint venture with the BP Pension Fund. Ropemaker Properties Ltd (the property nominee of the BP Pension Fund).
The new owners are clients of Wolfe Asset Management Limited. a wholly owned subsidiary of the Al Gurg Family which owns the business conglomerate Easa Saleh Al Gurg Group in Dubai.
"The sale of 240 Blackfriars Road is the culmination of an exceptional development project for GRP," said Toby Courtauld, chief executive of GPE.
"Having secured an attractive planning permission in March 2011, GRP commenced development in January 2012 following the pre-letting of 105,825 sq ft to UBM Plc. The sale continues our strategy of recycling capital out of assets where we have created value."
Abdulla Al Gurg, group general manager of WAML, said: "The 240 Blackfriars Road building is iconic in its design and an instantly recognisable feature of the London skyline. It perfectly fits within our strategy of owning best in class commercial buildings in prominent London locations.
"Southbank is regarded as one of London's most vibrant districts and thriving sub-markets, with a unique combination of world renowned arts and theatre institutions, hotels, luxury residential developments, excellent connectivity and prime real estate.".