Union boss Mick Cash has accused Greater Anglia of planning to use a “scab army” of managers and back-office staff to keep trains running next week.

And the RMT general secretary has also claimed the company is compromising safety by using back-office staff to work as conductor/guards during the two one-day strikes next Tuesday and Thursday.

He said: “This is effectively a scab army of poorly trained managers, with corners cuts and safety compromised.”

Greater Anglia have insist that customers should not notice a change to their service anywhere on the network.

Director Richard Dean said: “Our back office staff have gone through a rigorous training process, and have to pass competence, medical and safety tests before they can stand in for conductors. We will also have extra managers at stations to help customers with any enquiries.”

Greater Anglia have said that they have guaranteed conductor jobs until the end of the franchise in 2025.