Tata Steel has already commenced deliveries and will ultimately supply more than 57km of its Stress-Free heat-treated, wear-resistant rail for the project.

The line will link Reading and Heathrow Airport in the west with Shenfield and Abbey Wood in the east via a new 21km twin-bore tunnel beneath central London.

During 2015 major tunnelling works will conclude and the focus will shift towards fit-out and installation of railway systems within the tunnels and stations. An Alstom-TSO-Costain joint venture (ATCjv) has been appointed to fit out tunnels with the contract including power supplies and electrification.