Arcadis Hyder, CH2M Hill and Aecom are among the consultants chosen by TfL to further develop plans for Crossrail 2.

The proposed rail route is planned to run from north-east London to south-west London and is being developed by TfL and Network Rail.

It has been estimated to cost £27.5bn.

London mayor Boris Johnson has said: “this project could have major benefits for London, helping to boost rail capacity and the creating of new jobs and homes in the capital and beyond.”