The rail regulator has said that the £9.8 billion upgrade of the West Coast Main Line could be delayed for a year to save money

Passengers could face a further delay in the introduction of high speed rail journeys, Tom Winsor warned.

Forum Response: Association of Train Operating Companies

George Muir, director general of ATOC, said: "Network Rail must become more efficient, but equally, they must get enough money to do the job. A reliable railway is a good investment for the country.

"This is a tough judgement from the regulator. There is a good management team at Network Rail and we must wait and hear their considered response.

"The suggestion of a delay to upgrading the north end of the West Coast Main Line is of concern. You can't play stop-go with big projects like this. If the work is ready to start, do we really save money by delaying it?"

Forum Response: Virgin Trains

Chris Green, chief executive of Virgin Trains, "Virgin Trains would be deeply concerned over yet another delay to the West Coast upgrade and its benefits to passengers.

"We have invested £1 billion in new tilting trains and we now desperately need modern infrastructure from London to Glasgow to deliver a reliable 125mph tilting railway.

"Applying stop-go tactics at this eleventh hour can only damage the rail industry. We shall be responding vigorously in the consultation process."