Finance Secretary Shona Robison has sought to blame Westminster for a “whole new era of austerity” as she prepares to update MSPs on the scale of Scottish Government spending cuts.

The Cabinet secretary will update MSPs on Tuesday as Holyrood returns from the summer recess, with spending worth hundreds of millions expected to be cut as she attempts to fill a budget black hole.

However, opposition parties say it is the SNP’s own decisions which have led to the public finances being strained.

A number of measures have already been announced, with the Government redirecting money from a nature fund and a free iPad scheme to go towards local authority pay awards.

The First Minister has already warned there are more “tough decisions” ahead.

The independent Scottish Fiscal Commission has noted that more than half of the Government’s resource spending is allocated to public sector pay and above-expectation increases in this area will lead to cuts elsewhere.

Ahead of her statement, Ms Robison said: “The SNP Government has delivered a balanced budget in every year that we have been in office – and we will continue to do so.

“I am proud to serve in a government which is investing hundreds of millions of pounds to lift children in Scotland out of poverty, and is ensuring our police, our nurses and our teachers are the best-paid in the UK.

“We have taken many tough choices – including asking those on higher incomes to pay a bit more income tax – in order that we can invest more in public services like our NHS.

“But the fact is, the Scottish Government operates with a largely fixed budget determined by Westminster and, under the Labour Government, it is clear that we are entering a whole new era of austerity.

“The cuts that they are proposing to make will have a profound effect on our ability to deliver for the people of Scotland – but (the) SNP Government will do everything we can to protect people and public services from the cuts that Westminster is making to our budget.”

She added: “Were Scotland an independent country, we would not be paying the price for bad decisions taken at Westminster – whether that be years of austerity cuts, Brexit, or reckless mini budgets – all of which have taken money out of the economy and funding for public services.

“Scotland should be able to determine our own future, and we should have full the powers to invest in our people, our public services and the planet as a way to building a more prosperous country.”

Scottish Labour said there must be detailed explanations of the departmental budgets being cut.

Finance spokesman Michael Marra said: “With brutal cuts to services and potential job losses looming, the usual SNP secrecy and spin will not cut it.

“It’s time for the SNP to come clean about the financial chaos it has created and tell us the truth about what lies ahead.

“The SNP has said essential jobs would be protected from cuts, but it has failed to say in any way what an essential job actually is.

“This incompetence and failure to plan is causing uncertainty for public sector workers and chaos for service leaders, who now need urgent clarity.”

He added: “The SNP’s pathetic attempts to deflect blame have been demolished by experts – it must drop the excuses and take responsibility for its own failure.”

Scottish Liberal Democrat leader Alex Cole-Hamilton said: “This SNP Government have gone four times over budget building ferries, sold off Scotland’s prize seabed on the cheap and handed £50 million to an engineering firm that went bust.

“As a result, there is less money to go round for public services. They’re promising to spend millions on misguided plans to give ministers more control over care services.

“The nationalists have got themselves in a mess because their focus has always been on breaking up the UK, not delivering public services.”

Elections expert Sir John Curtice, a professor at Strathclyde University, said the issue of blame for the public finances would be a key part of the political debate in the coming years.

He told the PA news agency: “There will now be this battle between Labour and the SNP, about whose fault is it – and who gets the credit if things turn around.”

Sir John continued: “The SNP definitely have work to do.

“But equally, now Labour are power in Westminster, and given the path down which Rachel Reeves seems like to go and given the weakness of their electoral base, they face a challenge as well.”

A UK Government spokeswoman said: “We’ve been clear that tough decisions must be taken to restore economic stability and address the £22 billion hole in the public finances left by the last government. This is a challenge facing the whole of the UK, including Scotland.

“The Chancellor reiterated this in a constructive meeting with the First Minister and Finance Minister in Glasgow last week, and we are committed to working with the Scottish Government on our shared priorities to fix the foundations of our economy, so we can rebuild Britain and make every part of the United Kingdom better off.”

Scottish Conservative finance spokesman Liz Smith said: “It is the SNP’s financial mismanagement over their 17 years in power that has pushed public services beyond breaking point, yet the SNP leader acts like his party have done nothing wrong.

“They are solely responsible for record backlogs in our NHS, falling standards in our schools and councils having to cut day-to-day services year after year.”