A freeze on public sector pay would “sell out” millions of workers across the UK and lead to a fresh wave of austerity, Angela Rayner, has insisted ahead of the Chancellor’s set-piece spending review on Wednesday.

And the SNP’s Ian Blackford argued that any such pay freeze would be an “insult” to those on the frontline battling Covid-19 and called for a fiscal stimulus package of at least £98 billion to boost the economy to recovery.

Labour’s deputy leader, who was a care worker before becoming an MP, took Rishi Sunak to task after he insisted that this week’s key economic statement would not represent a return to austerity given the tens of billions of pounds of extra spending set to be announced.

Yet, the Chancellor has not disabused people of the idea that he is also about to confirm a three-year pay freeze for public sector workers; frontline NHS staff excepted. This could raise as much as £23 billion.

Mr Sunak’s argument is likely to be that private sector workers have seen their pay fall in relative terms and, as the country needs to tighten its belt to begin to pay back the debt built up in response to the pandemic, then the public sector will need to take its fair share of pain.

However, Ms Rayner was having none of it and, speaking to an online rally for fair pay, called on the UK Government to end “poverty wages” that workers could barely survive on and increase the minimum wage to a level that people could live on; “a real living wage of at least £10 an hour”.

Commenting on the prospect of a public sector pay freeze, Ms Rayner said: “The Chancellor says a pay freeze for millions of the key workers who have put their lives on the line through this crisis is not a return to austerity. He is wrong.

“Tell that to the care worker trying to feed their family on £8 an hour. Tell that to the hospital porter or the teaching assistant struggling to pay the bills and put food on the table.

“Tory ministers fell over themselves to clap our key workers when the cameras were rolling and now, they want to sell them out.

“Under this government our key workers are getting their pay frozen whilst ministers are handing out contracts to their mates. It’s a disgrace and the Chancellor must think again before the Spending Review on Wednesday,” declared the Greater Manchester MP.

She argued that the pandemic had shown society could not survive without its key public sector workers, whom she described as the “real backbone of our economy”.

Ms Rayner added: “Nobody should be working for poverty wages. Every worker should be paid a wage that they can actually live on, and that means a real living wage of at least £10 an hour now.”

Earlier, her colleague Anneliese Dodds in a speech urged Mr Sunak to “get a grip” on wasteful pandemic spending rather than looking to freeze the pay of public sector workers.

The Shadow Chancellor called on him to use the spending review to treat frontline workers “decently, rather than grinding them down”.

Trade unions have already warned of possible strike action should Mr Sunak impose a pay freeze.

Meanwhile, ahead of the spending review the SNP has called on the UK Government to introduce a fiscal stimulus package of at least £98bn to kick-start the economy.

In a letter to Boris Johnson and the Chancellor, Mr Blackford, the Nationalist leader at Westminster, also said the Tories must ditch plans to impose a public sector pay freeze but, rather, deliver a major investment package to "protect our public services and put money in people's pockets".

He insisted there must be no return to Tory austerity, which would starve the economy of cash at the worst possible time ie amid a devastating extreme Brexit and growing Tory unemployment crisis.

The SNP is calling for:

*a fiscal stimulus of at least £98bn and the devolution of financial powers to secure a strong, fair and green recovery, and mitigate the damage of Brexit, which had already taken £4bn out of Scotland's economy;

*a package of measures to put money in people's pockets, committing to extend the furlough scheme until the end of 2021 if required, making the £20 uplift to Universal Credit permanent and extending it to legacy benefits, fixing the gaps in Covid-19 support schemes for the three million people excluded, and tackling child poverty by introducing an increase in benefits modelled on the new Scottish Child Payment of £10 per child per week and

*a major cash injection for the NHS and social care across the four UK nations by increasing the level of spending on health and social care in England to at least the higher per capita level in Scotland, resulting in an extra £4bn for NHS Scotland and enabling a pay increase for workers across the UK.

"At a time when the UK faces a devastating extreme Brexit and a growing Tory unemployment crisis, it is crucial that the Chancellor uses the spending review to deliver a major fiscal stimulus package and the devolution of financial powers to protect our public services, put money in people's pockets, and kickstart a strong economic recovery,” said Mr Blackford.

"Talk of a return to Tory austerity cuts, with a public sector pay freeze, is an insult to millions of workers who have been on the frontline in the fight against Covid-19. It would squeeze living standards and starve the economy of investment at the worst possible time when we need a stimulus of at least £98bn to match other countries,” he added.