Demolition work is now underway on the site with main construction set to start in the New Year.
Work will see the demolition of the existing offices and the construction of a new eight-floor office building including a Category A fit-out and the addition of 13,000sqm of retail space on the ground floor.
As part of the works, the entrance to Mansion House underground station will also be refurbished as it sits on the site.
Arnaud Bekaert, Bouygues UK’s Managing Director for Construction London and South East said: “We have a solid reputation for taking existing office sites and redeveloping them to maximise the commercial space available for clients.
“This in turn is helping businesses to meet the continued and growing demand for more offices in the capital.
“We’ve recently completed our office building at Queen Victoria Street; signed a deal to deliver new apartments for The Hempel Collection in Bayswater and handed over the last of 17 schools that formed part of the Tower Hamlets Building Schools for the Future Programme.
“That, coupled with the work that my colleagues are doing on the Housing and Development side of the business means that we’re diversifying and consolidating our already strong presence in London and the South East.”
The project is due for completion in 2016.