Union members are preparing to protest outside the Scottish Parliament amid claims the council tax freeze will cost local authorities £484m and thousands of jobs.

The Scottish Government said it has given local authorities more than enough money to cover the cost of the council tax freeze but the GMB union said budgets have not kept pace with inflation and poorer households are paying more than the rich.

The GMB said the cuts will result in nearly 9000 job losses next year, while the Unite union said they will cost 15,000 jobs.

Deputy first minister John Swinney insisted the reduction in local government expenditure would "have minimal impact on jobs or services".

Unions have described Mr Swinney's statement as "insulting" and have organised a protest to coincide with the final reading of the Scottish Budget next week.

The GMB claims that had council tax kept pace with inflation of 25.61% since 2007, Scotland's 32 local authories would raise £484m in additional income for 2016-17.

GMB Scotland secretary Gary Smith said: "Government ministers need to take their heads out of the sand about the devastating impact of the cuts they are making on essential local services right across Scotland.

"GMB research suggests that more than 8,000 jobs could be lost if the current Budget cuts are carried next week. For John Swinney to describe that as 'minimal' is simply insulting to every local government worker and every local community in Scotland. "

The union has backed Labour's plan for a 1p rise in income tax with a rebate for the lower paid - a rebate that Mr Swinney insists cannot be delivered.

Unite regional officer Willie McGonigle said: "To suggest the Budget cuts will have 'a minimal impact on jobs or services' is frankly astounding.

"We've lost 40,000 local government jobs since 2010 and over the next year we will likely lose a further 15,000 as a result of the Scottish Government's cuts.

"The impact on local services and livelihoods will be significant and there is no getting away from this, however much the Scottish Government may try to do so."

Scottish Labour public services spokeswoman Jackie Baillie said: "The SNP are in complete and utter denial about the damage their Budget will do to Scotland.

"As councils up and down the country are forced to make swingeing cuts to jobs and services because of the SNP Budget, for John Swinney to claim that any impact would be minimal is simply laughable."

In a written answer to parliament, Mr Swinney said: "The package of funding the Scottish Government is providing for the financial year 2016-17 to local government will enable councils to increase the pace of reform and improve public services to communities across the country.

"Taking into account the addition of the £250m to support the integration of health and social care, next year's reduction in local authority overall estimated expenditure is less than 1%.

"I believe that such a reduction should have minimal impact on the jobs or services as Scotland's councils should be able to address these challenges from a healthy base as local government funding has been rising in Scotland in recent years."

A Scottish Government spokesman said: "Scotland's local authorities agreed to a financial settlement which, when taken together as a package of funding, will enable them to increase the pace of reform and improve essential public services to communities all over the country.

"Local government has been treated very fairly by the Scottish Government and protected from the worst impact of UK cuts, despite cuts of nearly 9% to the Scottish budget from the UK Government.

"Taking into account the addition of the £250m to support the integration of health and social care, as a percentage of estimated total revenue expenditure, next year's reduction in local authority overall estimated expenditure is less than 1% and does not take account of the additional money that we are investing in educational attainment over and above councils' core school budgets."

He added: "The Scottish Government has fully funded the council tax freeze, indeed recent independent research from the Scottish Parliament's Information Service found that, compared to inflation, we have over-funded the council tax freeze by £164.9m since 2008."