WALES' main rail operator has urged passengers to only make essential journeys on some routes this Saturday, when the network will be hit with a fresh round of strike disruption.
Train drivers' union ASLEF will stage walkouts at several companies across Britain on July 30, amid accusations firms have failed to make a pay offer to help members keep pace with increases in the cost of living.
Transport for Wales is not directly involved in industrial action, but is expecting services to be "extremely busy as a result of the severely-reduced timetable put in place by other operators".
Services on the South Wales Main Line between Newport and Swansea are expected to be "very busy" because there will be an "extremely limited" number of Great Western Railway trains between Newport and Cardiff, and no GWR trains between Cardiff and Swansea on Saturday.
Transport for Wales said it would run additional services to try and improve capacity.
There'll also be a "particularly busy" route between Shrewsbury and Birmingham, where the 2022 Commonwealth Games are taking place, because West Midlands Railway is also not operating on Saturday.
Passengers wishing to travel on both these routes should only make essential journeys, Transport for Wales said.
Mick Whelan, the general secretary of ASLEF, said strikes were "always the last resort".
He said: “We don’t want to inconvenience passengers – our friends and families use public transport, too – and we don’t want to lose money by going on strike but we’ve been forced into this position by the companies, who say they have been driven to this by the government.”
A row broke out between unions and the UK Government's transport secretary Grant Shapps, after he laid out plans to curb industrial action, including stopping coordinated industrial action, limiting picketing, and having a cooling off period after strikes.
Saturday's strike will follow a series of pickets by the RMT union over pay and working conditions. Again, those strikes did not involve Transport for Wales, but much of the nation's train services were cancelled because Network Rail was affected.
Additional reporting by Alan Jones, PA industrial correspondent
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