The joint venture will be responsible for completing the detailed design, construction and planting of the new crossing.

Bouygues and Cimolai have been working with the Garden Bridge Trust since April 2015 when they were appointed for preconstruction services.

Main construction work on the Bridge is planned to commence this summer and to be completed in late 2018.

Lord Mervyn Davies, Chairman of the Garden Bridge Trust, said: “The Garden Bridge is a reality. We are on course with our fundraising targets, we are meeting the requirements of our planning conditions.

“We have huge public support for the project and we look forward to working with Bouygues TP and Cimolai and all our partners to make this a special place to be enjoyed by Londoners and visitors in the heart of the city for years to come.”

Bouygues TP and Cimolai are supported by Flint and Neil and Moxon Architects as designers.

Arup, Heatherwick Studio and Dan Pearson Studios will continue to provide advice to the Trust about the Bridge design and construction.