A Network Rail spokesperson said:

“Today Network Rail welcomes the support of the Office of Rail Regulation for our maintenance re-organisation. An efficient railway is a safe railway. As the ORR clearly says, the principles of our changes are sound and appropriate.

“The ORR has done a thorough job on auditing our proposals and where they have raised concerns we are addressing them. Working together, we are all committed to a safe, efficient and reliable railway. Unnecessary and unwanted strike actions jeopardise the progress we have all made in transforming the railway for the British people.

“Union leaders who defend out-dated work practices from the 1950s are standing in the way of that progress. This is the digital age not the steam age so we need to change so we can deliver the railway Britain needs in the 21st century.”