A £3 million Scottish Government free rail fare scheme could collapse if ScotRail refuses to fund the majority of the project, MSPs have heard.

Abellio ScotRail managing director Phil Verster told a Holyrood committee he "couldn't vouch" for the scheme going forward, though he said he does not foresee the Government having to find funding elsewhere.

He told the Rural Economy and Connectivity Committee he first heard of the initiative to give yearly and weekly season ticket holders a week's free travel "two to three weeks" before Transport Minister Humza Yousaf announced it.

Read more: Rail services “simply not good enough” as fares rise

Mr Verster said there are plans to use £1.8 million from the Service Quality Incentive Regime (Squire) railway improvement fund, which had been earmarked for "other initiatives", to pay for part of the project.

The Abellio ScotRail alliance controls the fund, which is built up through penalties imposed for delays and currently stands at around £1 million.

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'?"

Read more: Rail services “simply not good enough” as fares rise

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 is 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 Rona Mackay 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.

Mr Verster replied: "We have a very constructive relationship with Transport Scotland and the Scottish Government. A very open relationship.

Read more: Rail services “simply not good enough” as fares rise

"Now while we set may priorities of what we think would be best for customers, if Transport Scotland engages with us and makes alternative suggestions, of course we consider that.

"I don't think there's anything inappropriate about that. I think what is important is only one thing and that is customers in the end."

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