COMMUTERS face months of misery after transport bosses refused to say how long carriage cuts on the country’s busiest rail route will last.

Transport minister Humza Yousaf said health and safety was his “number one priority” – but insisted it would have taken a crystal ball to foresee some of the latest problems.

It comes after rail bosses announced the number of coaches on the main Edinburgh to Glasgow line would be slashed.

They said some trains had reached the end of their lease and were now being transferred elsewhere in the UK.

Meanwhile, long-promised Class 385 electric models – which were due to be brought in last year – have faced delays and safety fears.

Mr Yousaf said he was unable to say when services would return to normal, but insisted capacity issues would be mitigated by the introduction of high-speed trains from May onwards.

Scottish Liberal Democrat transport spokesman Mike Rumbles called on ministers to set a deadline on resolving the issue, with “repercussions for the company in the event that ScotRail fail to deliver once again”.

He said: “The carriage crisis is having a serious impact on the thousands of commuters that depend on this service, and it is entirely possible they will have an especially tough few days as the Siberian snow conditions close in.

“The minister’s assertion that ScotRail and Hitachi are working on the issue doesn’t offer any credible guarantee given how far he has overshot his previous promises to deliver a fully operational fleet by last December.

“The minister dodged the question twice and refused to set a deadline for the conclusion of this capacity crisis. He has offered little reassurance today to the commuters who face the unenviable choice of getting on packed trains or taking the long route.

“I want to see a clear plan and timetable for when this will be resolved so that busy working people can get on with their lives without worrying about administrative incompetence. This should include repercussions for the company in the event that ScotRail fail to deliver once again."

ScotRail said ten trains a day will now run with fewer carriages, with peak services reduced from six coaches to just three or four.

In a bid to lessen the strain, a reduced £13 fare will be brought in on the Glasgow Queen Street to Edinburgh via Airdrie line.

New Class 385s were due to be introduced last autumn but have faced manufacturing delays, as well as safety fears over their curved windscreens.

Mr Yousaf admitted there would be “short-term” capacity problems, but insisted train manufacturer Hitachi and ScotRail were working “tirelessly” to get the new fleet up and running.

He said: “I absolutely regret the inconvenience that’s been caused to passengers. Issues around the supply chain with Hitachi, a global company, have been the primary factors in the delay that we’re seeing.

“But frankly I don’t think passengers care who’s to blame. They want to see the new trains introduced, and that is what I’m working to do. But I cannot compromise safety.”

He said new trains were currently going through testing, while ScotRail had managed to extend some leases and ensure the “impact is not as bad as we first feared”.

And he pledged the Class 385s and high-speed trains would add “an enormous amount of additional capacity, which passengers will feel”.

Mr Yousaf added: “We expected Hitachi, the train manufacturer, to deliver these trains last autumn.

“And in fairness to ScotRail, they have built in five months – almost six months – of additional time at the end of the lease.

“You would have to have some crystal ball to envisage some of the problems that Hitachi have been facing as a global company.

“I have to say, I’m astounded at some of the problems they’ve been facing in terms of supply chain and in terms of productivity at their new plant.”

He insisted ScotRail had “done their best” to extend some of the leases in the current train stock, while transport leaders were prepared for the worst case scenario.