Speaking after today's Rail Accident Investigation Branch Report confirmed that faulty points were the cause of Friday's accident at Grayrigg, RMT general secretary Bob Crow said: "There are frightening similarities between Grayrigg and the Potters Bar crash in 2002.

"The government has shamefully resisted calls for a public inquiry into Potters Bar. Yet internal industry inquiries have clearly proved insufficient to stop a repeat of that tragedy.

"We need to get all the facts out into the open. Nothing less than a full public inquiry will do," Bob Crow added.

The union believes that any public inquiry must examine the adequacy of Network Rail's management systems because of the fragmentation of engineering work that still afflicts Britain's railways.

It is often unclear, for example, which track employees have worked in the vicinity of a site. A total of 92,000 workers from a myriad of different engineering companies have access to the trackside across Britain's rail network.

The union warned that should the government fail to order a public inquiry, RMT will take the matter to judicial review.