The next generation of high-speed broadband mobile phones, due to be launched from 2014, could compromise rail safety in Britain, ministers were warned yesterday.

Lord Berkeley, chairman of the Rail Freight Group, said it “could be a serious issue for the railways – it could cause accidents, ‘going through signals at red’ in the old terminology”. Lord Berkeley told peers there could be “serious problems of safety and operations” on the railways.

“It’s not much use if you have got super fast broadband which prevents super fast trains – or even ordinary trains – from running,” he said.

Lord Berkeley said the planned 900MHz spectrum for mobiles was “quite close” to the recently-introduced digital radio system used on the railways.

The railways’ roll-out was now “largely complete”, with 6,000 drivers’ cabs currently being modified, with funds from the government’s transport department.

The “worst-case scenario”, he said, was that it could cost up to £100 million to contain and eliminate interference to trackside and train systems.

He argued that this cost should be borne not by Network Rail but by either the transport department or the Department for Business, Innovation and Skills, which was promoting the fourth generation (4G) broadband auction.

“It is extraordinary that things have got this far,” he told peers. “We seem to be getting into a situation where, on the railways and the broadband, we are seeking to comply with EU-wide rules which appear to conflict.

Lord Berkeley, a former public affairs manager for Eurotunnel, said the problems of interference could occur within a distance of four kilometres of any railway infrastructure.

Two independent European studies had already shown that 900MHz broadband interfered with radio signals between trains and signallers, he said. “Because this is a safety-related issue, it is extremely important.