The region is being carved up between VolkerFitzpatrick, Costain, BAM Nuttall and Geoffrey Osborne.

It has now emerged that VolkerFitzpatrick is the major winner of the four partner contractors, taking the Anglia Route, estimated to be worth £480m.

The framework agreements cover almost half Network Rail’s £2.5bn workbank for the 2014-19 funding period in the region.

This includes delivering longer platforms for longer trains on key commuter routes, station enhancements, new footbridges to improve accessibility and upgrades to bridges, embankments and tunnels.

Cost estimates for each of the deals have been upwardly revised by 20% since they were first advertised.

BAM Nuttall’s Sussex region and Osborne’s Wessex region improved are each worth around £276m.

While Costain on the Kent route is expected to deliver work worth £144m.

The CP5 framework comes into force on 1 April 2014.

These latest frameworks agreements have been designed to encourage increased collaboration between Network Rail and its partners.

They set out shared objectives to enable both sides to share in risk and reward and to incentivise safe, efficient project delivery.