The Scottish Government has pledged to do everything it can to protect families north of the border from further austerity measures to be announced by the Chancellor.

Ahead of George Osborne revealing details of his Autumn Statement and Spending Review, Scottish Deputy First Minister John Swinney said ministers at Holyrood would do "everything within our power to protect the most vulnerable".

Mr Osborne will this afternoon explain how the Conservative Government plans to make £20 billion worth of spending cuts and £12 billion savings on welfare.

The cuts are intended, along with a £5 billion crackdown on tax avoidance, to meet the Chancellor's pledge to eliminate the national deficit without raising personal taxes.

But Mr Swinney insisted that the Conservatives are "engaged in austerity of choice, not necessity".

He said: "The Scottish Government has consistently demonstrated that the UK's deficit and debt can be brought down without the need for huge public spending cuts as set out by the UK Government. We have set out that the public finances can be returned to a sustainable footing alongside increasing public sector net investment."

He said the likelihood is that the Chancellor will make a "significant real-terms cut to Scotland's budget" and added: "What is worse is these cuts will hit the poorest the hardest.

"Low-income working households with children are set to lose an average of £1,500 a year if the cut to tax credits goes ahead. A short-sighted move that will have a damaging impact to families who already struggle to make ends meet while simultaneously removing work incentives and inhibiting future economic growth.

"We will continue to do everything within our power to protect the most vulnerable from the UK Government's austerity measures, but we want to use our powers and resources to lift people out of poverty, not just continually mitigate as best we can."

With Scotland to get some limited power over income tax from April next year, with the ability to set rates and bands due in 2017, Mr Swinney said in the future Holyrood ministers would be able to "take a distinctive approach to the challenges we face".

Mr Swinney will set out his budget plans for 2016-17 in December, with the Deputy First Minister adding: "We will be fair and progressive in our decisions.

"We only hope and call on the Chancellor to take a fair and progressive approach to the Spending Review and end his obsession with needless austerity."

Shadow Scottish secretary Ian Murray also criticised Conservative plans to cut tax credits for working families.

Mr Murray, the only Labour MP in Scotland following the SNP's landslide victory in May's general election, said: "Before the election, the Tories promised that they would not cut tax credits, but their plans will cost three million working families £1,300 a year.

"Scottish Labour is clear that the Chancellor must reverse his decision, but if he does not we would use the new powers available to the Scottish Government to restore the money lost in full."

He added: "A Labour government would balance the current budget, but we wouldn't cut off our ability to invest in world-class infrastructure, support our world-leading science and technology sectors or encourage more research and development to fuel the jobs of the future."