SCOTRAIL’S operator will be stripped of the franchise if its performance does not get better, the Transport Secretary has warned.

Mr Matheson made the threat after Scottish ministers issued a remedial plan notice on Christmas Eve, demanding services improve.

It came after weeks of cancellations and delays as trains struggle under staff shortages caused by timetable changes and industrial action.

Dutch firm Abellio, which runs ScotRail, was given eight weeks to come up with a “robust” plan to get performance back on track.

Addressing the issue in Holyrood, Mr Matheson said he was committed to holding ScotRail to account.

But he insisted around half of the delays suffered by passengers are caused by Network Rail, which owns and manages the railway infrastructure.

He said ScotRail would have to submit its improvement plan by around February 18, adding: “If they fail to do that, then they are in breach of the contract.

“And ultimately, for any organisation when they are in breach of the contract, they could be fined or at the same time costs could be increased for certain services which they provide to the taxpayer.

“Or we could actually remove the contract from them. So this has got very serious implications for the contract holder.

“A remedial plan is not something you would issue just on the basis of a whim, of some individual problems on limited occasions.

“This is because there have been a series of problems over a period of time that I don’t believe is acceptable.

“In discussions I’ve had with ScotRail, they’re very clear about how serious this is for them.

“But they’ve also assured me that they’re determined to do everything they can to make sure they get the services back in line with what’s expected within the contract.”

Critics insisted the public would have little faith things will get better.

Scottish Liberal Democrat transport spokesman Mike Rumbles said: “Two years ago the previous Transport Secretary promised that he had a plan in place for getting Scotland’s railways rolling.

"Now his successor stands up and makes a remarkably similar promise.

“The public can have no faith in this SNP Government’s command of our railways when plans and promises come and go but performance continues to stall.

“Scottish Liberal Democrats demand better. We need a railway system that delivers for passengers who are paying through the nose for a substandard service.

“If there isn’t an immediate improvement Abellio should be stripped off the franchise at the first possible opportunity”

Scottish Labour’s transport spokesman Colin Smyth said Mr Matheson must take personal responsibility and apologise.

He said: “With prices rising and performances plunging, it is no surprise that more and more people are backing Labour's call to bring our railways into public ownership so we have a railway system run for passengers, not profits."

Scottish Greens transport spokesman John Finnie said: "It’s extraordinary that is has taken month after month of mismanagement by Abellio for the Transport Secretary to take this situation seriously.

“Talk of improvement plans will be of little comfort to commuters who’ve heard such promises before and who cannot rely on the rail services they need to get them to and from their work. We’re long overdue putting this public service back in public hands.”

ScotRail has offered free travel to season ticket holders on some of the “worst affected routes” over upcoming weekends to apologise for its unacceptable performance.

It comes after rail fares across the UK were hiked at the start of January in line with inflation. Off-peak tickets in Scotland rose by a smaller amount than elsewhere due to a decision to cap rises at 2.2 per cent.

ScotRail's popular Kids Go Free scheme was also scrapped and replaced by Kids for a Quid.