SNP asked to find extra £150 million in budget or lose Green's support
Since the SNP is a minority government, they must gain three votes from another part in order to pass the budget.
The Greens are seen as the most likely to back the budget, as they supported last year's. However, their support was only won after two-months of negotiations saw the government make concessions totalling £220m of extra spending - including £160m for local authorities.
Green MSP Andy Wightman said "We want a real terms increase (in council budgets) and that would involve somewhere in the region of £150m as I calculate it this morning".
This figure is similar to the £153m that council body Cosla says has been cut from council budgets in real terms, although Mr Wightman said there were "various figures".
In Thursday's budget, a 3% council tax increase was offered to local councils to use if they wish, if they choose to implement the rise, then funding for local authorities could be covered.
Public-sector trade unions are dismayed that Mackay did not increase funding for Scotland’s 32 councils to allow them to match an offer he made to other civil servants, police and nurses to increase their wages by up to 3%.
Dave Watson, a Scottish official with the public-sector union Unison, said pay policy “was moving in the right direction but it’s not been met with proportionate funding. What is absolutely clear is it is not funded at all for local government.”
Watson said it would cost councils roughly £210m to fund the pay deal, so the £150m extra being demanded by the Greens would be quickly swallowed up.
Negotiations of where the extra £150 million could be found are ongoing, leading to speculation of a further taxation rise.