The theft of metal has caused the delay or cancellation of over 35,000 national rail services in the last financial year

MPs of all parties are intensifying demands for the government to act to combat metal theft by stopping cash transactions in the scrap metal industry and making sellers provide ID.

The House of Commons transport committee says dealers are the weak link in efforts to prevent metal theft ? a crime that caused the delay or cancellation of over 35,000 national rail services in the last financial year.

Louise Ellman, chair of the transport committee, said: "Cable theft from the rail network is part of an increase in metal theft across the country, made easy by the way in which stolen metal can be sold to scrap metal dealers.

"Current legislation for regulating scrap metal dealers is out of date. We need urgent reform to improve the audit trail generated by the scrap metal industry so that criminals selling stolen metal into the trade can be identified much more easily."

The committee recommends that all individuals should provide proof of ID before any sale of metal, and calls for extra search powers for transport police to enter scrap metal sites, as well as a new offence of aggravated trespass on railways to target cable thieves.

It also calls for greater clarity around compensation arrangements for the travelling public. The current system potentially allows train operators to profit from disruption caused by cable theft.

Reports this week have suggested that the home secretary, Theresa May, is considering abolishing the maximum ?1,000 fine for illegally trading in scrap metal. One tonne of copper now trades for over ?5,000.

The British Metals Recycling Association, the industry body for scrap dealers, said it supported government efforts to update current legislation - the 1964 Scrap Metal Dealers Act - but said it was "only one piece of the jigsaw", and it was more important to crack down on the many illegal dealers, rather than drive more trade into their hands.

A Home Office spokesperson said the government had stepped up enforcement action, but believed legislation was needed. "We are currently looking at a range of options including what would be the quickest and most effective legislative vehicle for the changes that are needed."

Labour said plans for bigger fines and ID were not enough, arguing police needed tougher powers to close rogue traders down.