TRAIN drivers are to stage a fourth week-long overtime ban next month over pay, their union Aslef announced today.

The union warned that the action, from July 31 to August 5, will “seriously disrupt services” because profiteering operators refuse to employ enough drivers to fulfil timetables.

Operators have been accused by the union of exploiting an overtime agreement, intended to provide training for new drivers, using it instead to maintain timetabled services.