THE redevelopment of one of Scotland's busiest rail stations is already facing major delays after MSPs were told that "significant risks" had been identified.

The man in charge of the country's rail services told a Holyrood committee it would be several more months before he could tell them how long the hold-ups to the overhaul of Glasgow's Queen Street Station would last.

It comes amid major concerns raised about the planned one month’s free travel for monthly and annual season ticket holders, announced recently by the Scottish Government.

ScotRail chief Phil Verster said the operator had yet to agree to provide £1.8million of the £3m cost of the scheme, the contribution coming from the Service Quality Incentive Regime (Squire), a rail improvement fund generated by fines paid by the train operator for failing quality checks.

He told the committee he first heard of the initiative "two to three weeks" before Mr Yousaf announced it.

Mr Verster said the Squire fund is controlled by ScotRail, with the pot currently standing at around £1m.

He also told Parliament's Rural Economy and Connectivity Committee that work on Queen Street had been due to start in December but it would be a further three months before he could commit to a date.

Mr Verster told MSPs: "There is a significant risk which we have not been able to size currently which will be resolved in the coming months.

A report on the administrative nand contractual end of the redevelopment has been cited as the reason for the delay. It had been due to be forwarded to the country's transport minister in July but will not be on Humza Yousaf's desk now until February.

The Scottish Government announced the free travel scheme in the aftermath of the draft budget in November and again when fares were raised at the start of the month.

During questioning of Mr Versterm SNP MSP Christine Grahame said: "You can if you like, because you're a commercial company, say to the minister 'You're not having it'. Are you going to do that?"

Mr Verster replied: "We are busy discussing this with Transport Scotland and I prefer not to commit to a position yet."

Ms Grahame said: "So the scheme might not go ahead because you've not decided 'Yes, we're going to do this'?"

Mr Verster replied: "I can't vouch for whether the scheme goes ahead or not. I can just comment on whether we will make that decision, and when we'll make the decision in the next couple of weeks in terms of how we will deploy the Squire fund."

He said he was currently working with the Scottish Government and Transport Scotland to understand how to fund the £3 million they have identified, and had not thought of using Squire for the fares scheme before the Government suggestion.

Labour MSP Rhoda Grant said: "This is quite extraordinary. I was going to say this is policy made on the back of a fag packet, but I don't think it's even reached that stage of development."

Liberal Democrat MSP Mike Rumbles said he had assumed the Scottish Government would be paying for the free fares scheme.

He said: "It's not new money that the Scottish Government is using, it's money that you were going to invest in the railways."

He said it was "completely inappropriate" for the Transport Minister to ask for the money and it should up to Abellio ScotRail how to spend it, not the Scottish Government.

A Scottish Government spokesman said: “The ScotRail contract permits Squire funding to be directed to initiatives that improve the customer service experience, and we are currently negotiating the terms of the fares initiative with Scotrail through Transport Scotland, with the details expected to be finalised and announced in the coming weeks.”

Mr Verster also told the committee he expects to hit the 90.3 per cent Moving Annual Average (MMA) threshold in March, having risen 0.5 per cent in the past three months.

The MMA is a rolling measure of punctuality and reliability over 12 months and it falling below 90.3 per cent is a trigger for Transport Scotland intervention.

Mr Verster could not say exactly when he expects to hit the 91.3 per cent MMA franchise target.

He told MSPs: "I expect us by March to have cleared 90.3 per cent at least, the point that was the original trigger level, and to continue to improve from where we are.

"I can't tell you exactly when we will be at 91, 91.3, or 91. But what I can tell you, that we will continue to put plans together that will be live and throughout the next year continue to improve our MMA."

He said 733 out of 1,266 actions in the improvement plan had been completed.

The Transport Minister had been due to appear before the committee but was unable due to illness.