Green leader Patrick Harvie and his colleagues have insisted on the cancellation of road projects

The SNP government is preparing to shun its pro-independence allies, the Greens, in this week’s budget, with a surprise deal involving Labour and the Lib Dems potentially on the cards.

Finance secretary Derek Mackay is set to unveil the Scottish government’s budget on Thursday afternoon, with MSPs voting later in the day.

Since 2017, Nicola Sturgeon’s administration has relied on the Greens to secure a Holyrood majority for its budgets. But this year Green leader Patrick Harvie and his colleagues have insisted on the cancellation of road projects at what SNP ministers regard as a “fanciful” price for their support. Ministers fear that cutting spend on such infrastructure would damage economic growth.

Labour’s finance spokeswoman Rhoda Grant said her party has an open mind about