Services were disrupted on several lines in Strathclyde yesterday and four stations were closed.

ScotRail said the problems were caused by a shortage of drivers willing to work overtime.

The operator conceded that it was their ‘contractual right’ not to volunteer for extra duty, but it was forced to amend the timetables on lines from Helensburgh Central, Lanark, Balloch and Milngavie, while no trains called at Airbles, Barnhill, Alexandra Parade or Duke Street. Other services were also affected, with approximately 25 per cent of trains cancelled.

Two days earlier ASLEF had warned ScotRail, which is owned by the Scottish Government, that it would recommend a ballot of its members to its Executive Committee because of a pay dispute.

ScotRail service delivery director Mark Ilderton said: ‘We’re sorry for the inconvenience caused to our customers. We know how frustrating it is when cancellations occur.

‘We hope that these service alterations will give customers some certainty and reliability when planning their journeys. Customers should check their journey on our website and mobile app before they travel and should also bear in mind that services will be busier than usual.

‘We want to resolve the pay dispute matter with trade unions and will remain fully committed to further discussions.’