ITF general secretary, Stephen Cotton, said: "The behaviour of Go Bus is nothing short of pathetic. This kind of draconian action - locking people out of work - should have been consigned to the past. All reasonable people will agree that this is no way to resolve a dispute, and no way to treat your workers.

"I represent 20 million transport workers and I call on Go Bus to end this action with immediate effect. I call on them to listen to the justified concerns of their workers and sit down and work this one out."