Strikers had their duties covered by trained and experienced signallers. Some signallers have also reported for work as normal and chosen not to take part in the unnecessary strike.

Chris Rayner, route director for Network Rail said: “We are determined that passengers won’t have to pay the price for this futile strike.  We will continue to work hard over the next few days to make the trains run.  We will also be providing support for any signallers who want to work as normal.

“There are exciting times ahead to give people in Wales better journeys, and this is a pointless distraction from getting on with our work to deliver the service passengers expect.  There’s still chance for the union to call off this strike and meet with us to find a sensible solution.”

The strike action is due to end on 19 December, Saturday.