THE Liberal Democrats have come under attack and accused of “political posturing” for using their opposition to a second independence referendum as grounds for refusing discussions with Finance Secretary Derek Mackay over his Budget proposals.

Andy Wightman, local government spokesman for the Scottish Greens, made the criticism after it looked uncertain the Scottish Government would reach an agreement with another party to back its financial plans when they are voted on today.

The SNP govern as a minority administration and need the support of MSPs from other parties to get its legislation through Holyrood.

READ MORE: Mackay urges Holyrood to act 'responsibly' over Budget

For the last two years the Scottish Greens’ six MSPs have backed the Scottish Government’s Budget plans in return for certain conditions including more funding for local government.

However, at the end of the 2018 process the party’s co-convener Patrick Harvie said it was the last time they would back the Budget during the current parliamentary term unless the Scottish Government made “meaningful progress” on local tax reform.

Speaking yesterday afternoon Wightman pointing to a report in yesterday’s Times which said Labour’s local government spokesman Alex Rowley had written to Mackay to suggest Labour would back the Budget if local councils got an extra £340m.

Wightman said the move by Rowley - which was met with disapproval by his party leader Richard Leonard - suggested that some figures in Holyrood were open to a more collaborative approach.

“I commend Alex Rowley for doing that. I think it shows he appears to take this process seriously and is willing to engage.”

But rounding on the Lib Dems, he said: “Asking the SNP to actively surrender a proposition for an independence referendum, which they have an electorate mandate for, I think is an unreasonable request. I think it’s posturing and I don’t think the Liberal Democrats have treated the Budget process seriously.”

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In contrast Wightman said that the Greens’ opposition to the Budget was “legitimate” as it was directly related to concerns over local government financing.

“As things stand we won’t be supporting the Budget,” he said. “Yes there is a prospect we will reach a deal in the next 12 hours, but the ball is in the government’s court.

“The government need three MSPs from other parties, and just because we don’t support it, does not mean it will not go through.”

He added: “It’s not good enough for opposition parties to posture and say the government is all bad, and we want nothing to do with them. I think it’s very irresponsible.”

Wightman appealed to Mackay to have round table discussions with other parties ahead of future Budgets to establish some agreed priorities.

“This is not the way we should be doing Budgets, “ he said. “What I believe should happen is that [every] September the Finance Secretary should convene a round table discussion with other parties to talk about what their priorities are and even lending opposition parties some technical support to work up ideas and then convene another round table so by the time I stood up and presented my draft Budget I would have some idea of what would command the support of opposition parties.”

A LibDem spokesman said: “The SNP’s own growth commission admits independence would mean less money for public services. That’s why we asked for brief cessation in their campaign for independence in exchange for budget negotiations. It’s a shame the SNP continue to put independence ahead of striking a progressive deal on local government, mental health and education.”

On Wightman’s calls for negotiations not to be left to the last minute, he added: “We first spoke to the Finance Secretary in the autumn making it clear what we wanted to see from the budget in terms of action on local government finance, mental health and education. He has known what it would take to get our support for months. It is he and the Greens who have taken this to the final hours.”