The figure is contained in the Office of Rail Regulation’s final determination of spending plans for Network Rail in the next five year cycle which starts in April 2014.

Network Rail will receive more than £21bn over the five years for day-to-day running but will be charged with cutting costs by 20% over the period.

Maintenance investment levels have been protected at £5bn and the regulator said savings “will not come at the expense of safety”.

The regulator said: “There will be around £250m to help improve safety of track workers, to be invested in new equipment and safer working practices.

“ORR has also approved an extra £571m to upgrade structures such as bridges and tunnels.”

The ORR has approved more than £12bn worth of enhancements to Britain’s rail network but £7bn of those schemes do not yet have clear delivery plans or costs.

The regulator is giving Network Rail until March 2015 to work up efficient plans for these enhancements before approving the funds.

New maintenance targets are also being set.

The regulator said: “ORR will set new regulatory targets for Network Rail’s asset management in key areas where performance needs to improve, particularly focusing on how it manages, maintains and renews the rail network.

“Better asset management will allow the company to move from a ‘find and fix’ approach to maintenance to a ‘predict and prevent’ way of working, helping to boost capacity and improve performance on the network.”

ORR Chief Executive Richard Price said: “Network Rail has made great strides in improving safety, performance and efficiency on Britain’s railways.

“Supported by significant levels of funding from governments, working more closely with the rest of the industry, and learning important lessons from the past, the company is capable of delivering more for customers and taxpayers.”

Network Rail chief executive David Higgins said: “We must now look at the individual targets within the determination, as well as the package as a whole and welcome the opportunity provided by the ORR to use the coming months to seek clarification and work through the detail.”