Greens want tax system changes before backing Scottish budget
Green MSPs have told the finance secretary he will need to make changes to income tax in Scotland if he wants them to help get his budget passed.
The party's Scottish co-convener Patrick Harvie said there was a "clear need" for new powers over income tax rates and thresholds to be employed.
He wants money raised this way to be used to boost local services.
The Scottish government said it would continue its "constructive discussions" with other parties over the budget.
This is the first year that Scottish government ministers have had new levels of control over taxation.
But with the SNP having lost its majority in the Parliament, finance secretary Derek Mackay needs to win support from opposition MSPs to get his tax and spending plans through.
Mr Harvie said the Greens wanted ministers to use the tax system "to reduce inequality in our society and to generate additional funds for public services".
Greens included plans to hike income tax to 60p for the highest earners in their manifesto for the 2016 Holyrood elections - which saw the party increase its number of MSPs from two to six.
Mr Harvie said: "While we and the SNP had very different proposals on income tax, the reality is we have a parliament of minorities, so compromise is going to be needed.
"However, it takes two to reach a compromise and the SNP's draft budget showed no effort to work with others.
"In discussions with ministers, we have outlined a range of options for them to make the tax system fairer, to reduce inequality in our society and to generate additional funds for public services.
"They have total freedom over rates and thresholds, and there is a clear need for them to use this flexibility."
Labour has already said it will vote against the budget because of cuts to local government.
Scottish leader leader Kezia Dugdale said the party could not back "a budget that cuts into our country's future".
The Tories have also signalled their opposition, saying the SNP's failure to raise the threshold for the 40p rate of income tax, as the Westminster government is doing, will make Scotland the "highest-taxed part of the UK".
Liberal Democrats have indicated they could back the government if Mr Mackay increases spending on key areas - including education, mental health and the police - by about £400m.
A Scottish government spokeswoman said they had published a budget "for growth and public services, for our environment and our communities".
She added: "It delivers increased investment in education, with £120m for schools to use at their discretion to close the attainment gap in 2017/18 - £20m more than previously announced.
"It delivers record investment in the NHS through an additional £304m in resource funding, £120m above inflation, as part of an overall commitment of an extra £500m above inflation over this Parliament. And it protects low income households from tax hikes and supports more and better jobs.
"We are in active discussions with other political parties about the Scottish budget. We are considering the detail of the propositions that we have received to date and will continue to take forward constructive discussions on our budget plans."