The big work boost will go to a joint venture between Balfour Beatty and Alstom trading as Signalling Solutions, which has picked up three of eight regions in the UK.

Another signalling specialist, Invensys, also secured three packages, and Atkins took two of the regional deals in the south.

Atkins estimated its part of the framework would be worth around £400m over the contract term.

The deals form the backbone of Network Rail’s programme to modernise and maintain safety-critical railway signalling systems and come into force from April.

The firms will deliver efficiency savings across the signalling work bank over the next seven years through further reductions in unit costs.

Simon Kirby, Network Rail managing director of infrastructure projects, said: “Network Rail is continuing to drive down the costs of Britain’s railway and is committed to meeting tough efficiency targets.

He added: “These new frameworks represent a seven-year commitment by suppliers, allowing us to work closely with them to develop long-term plans for work to be carried out more quickly and efficiently.

“The length of the agreements, coupled with a visible workload, will provide much-needed stability throughout the supply chain and drive further cost savings and innovation across our signalling renewals and enhancements activities.”

Integrated design teams and reduced man-marking will remove costly duplication of effort. Network Rail also plans to smooth peaks and troughs in its work bank to make better use of suppliers’ resources.

Balfour Beatty chief executive Ian Tyler said: “Network Rail is one of our key customers and we are delighted to have the opportunity to extend our relationship with them.

“The rail sector is of great importance to the UK and to us as a group and we look forward to using our strategic approach to innovation and collaboration in these important projects.”