Rail passengers have been urged to travel only if absolutely necessary as thousands of members of the Rail, Maritime and Transport (RMT) union at Network Rail will walk out from 6pm on Christmas Eve until 6am on 27 December.

The union said the industrial action would mostly affect planned engineering works, but Network Rail has said trains will stop running at around 3pm.

The AA predicts 16.5 million people will travel by road on Christmas Eve and have warned of lengthy delays, identifying the M5 between Bristol and Weston-super-Mare as one of the country’s worst stretches of roads.