Exemptions to a planned workplace parking levy could “quite possibly” be extended beyond the NHS to other parts of the public sector, the Scottish Government has said.

A spokesman for Nicola Sturgeon said the issue of whether other groups, such as teachers, should be excused from paying the new charge could be considered when the matter goes before the Scottish Parliament’s Rural Economy and Connectivity Committee.

He raised the possibility as the Conservatives demanded a “full consultation” be carried out on workplace parking charges and accused ministers of trying to “sneak” plans for a levy through the Scottish Parliament.

The Scottish Government has already committed in principle to support changes to legislation already going through Holyrood that will give councils the power to introduce a charge on workplace car parking.

That was part of a deal struck between the Scottish Greens and Finance Secretary Derek Mackay so the budget could pass at Holyrood.

SNP ministers insisted as part of the deal that any future levy will not be applied to hospitals and other NHS buildings.

Opposition MSPs have demanded to know why other public-sector workers, such as teachers, could end up having to pay the charge.

Ms Sturgeon’s spokesman said the exemption “could quite possibly” be extended.

He said this could happen because the details of the proposals for a workplace car parking levy have not yet been agreed.

The Tories said the Government had previously pledged to hold a consultation before any such charge was introduce.

In 2017, then-transport minister Humza Yousaf said there would be “conversations” ahead of a levy being implemented.

In November 2018, the current Transport Secretary Michael Matheson said the Government had “not consulted on the idea”.

Now Conservative finance spokesman Murdo Fraser has raised fears ministers could “sneak” the proposals through.

He said: “In 2017, they said they’d to listen to people’s views before considering whether to introduce this plan.

“Michael Matheson is on record just weeks ago admitting they haven’t done so.

“Yet now they want to sneak it through, all in order to buy off their friends in the Greens.

“A stronger Government would simply bin this badly thought out plan now. But if the SNP really wants to persist in keeping it going, it should at least do so with due respect for the people who will be affected.

“That means – as they promised – holding a full consultation, conducting an economic impact assessment, taking it out of the Transport Bill and allowing the Scottish Parliament to scrutinise it properly.”

The Tory added: “With every day that goes by, it’s becoming clear that Derek Mackay’s budget was scrawled by the Greens on the back of a fag packet.

“The car park tax is a complete mess. The SNP must, for once, listen to people and think again.”

The Scottish Government has agreed in principle to support Green amendments to the Transport (Scotland) Bill, which would give councils the power to bring in a workplace parking levy.

Ms Sturgeon’s spokesman stressed: “It’s the Greens who are bringing forward the amendment, it’s not a Scottish Government amendment.

“This was a Green proposal brought forward as a condition of their support for the budget. It’s not a Scottish Government proposal.”

He added members of the Scottish Cabinet had been “very pleased” that MSPs had voted in favour of the budget.

Scottish Greens transport spokesman John Finnie said: “My amendment to the Transport Bill will give local government the kind of power taken for granted in every council in England.

“Trusting our communities to raise funds in a way that suits local circumstances is clearly something that the Tories are scared of.

“I will be encouraging the Rural Economy and  Connectivity Committee to take evidence on my amendment so there is expert scrutiny of it.

“If a council chooses to introduce a workplace parking scheme, it would be up to that council to design a scheme and consult on it locally.

“It’s certainly my intention to draft the amendment in a way that exempts the NHS, as agreed with the Scottish Government.”

He added: “The Transport Bill is still at an early stage in the parliamentary process but ultimately it gives us a chance to empower local government and make Scotland fairer and greener.

“I’m not surprised it’s touched a nerve with the Tories, who have nothing constructive to say on these points.”

RAC head of roads policy Nicholas Lyes said: “If introduced, the workplace parking levy risks becoming a divisive tax on workers, many of whom have little alternative but to use their vehicles.

“Some two-thirds of commuters use their cars each day so there is a danger that many will have to fork out significant extra money every year if the vast majority of businesses choose to pass the tax straight on to their employees.”