THE SNP last night seized on figures buried in George Osborne's spending review to claim that the poorest in society will suffer most as a direct result of the Coalition's policies.

A background report produced by the Treasury to accompany the Chancellor's £11.5 billion cuts package for 2015-16 indicated that the poorest 20% of people take the biggest hit from the changes.

The "distributional analysis" painted a worsening picture for those in the country's bottom quintile since the March Budget, which forecast changes up to 2014-15.

The new Treasury paper showed only those in the bottom quintile will lose more money as a result of the spending review; all other income groups will lose less.

The Budget forecast that the bottom 20% of households would lose £830, or 3.4%, in 2014-15, compared with 2010-11, when the Coalition took office.

But the new spending round paper said they would be £930, or 3.9%, worse off in 2015-16 as a result of "changes to government policy".

The figures cover differences in tax, tax credits and benefits, as well as the benefits in kind that households get from public services.

It is cuts to this last category which appear to have had the biggest impact on lower-income households, as these rely most heavily on the state for education, health and care for the elderly.

Finance Secretary John Swinney said: "When the Treasury's own analysis accepts that the policies of the Westminster government are leaving poor families worse off, there can be no doubt that Westminster isn't working.

"This ideological drive that brands people shirkers and skivers when the majority of people on benefits are in work or retired is not something Scotland should have to accept.

"It is poorer households in poorer areas, who rely on public services and tax credits to top up their incomes from low-paying jobs, who are paying the price of Westminster's failure.

"That is simply not acceptable in Scotland. Westminster's continued economic failure is hitting family budgets, public services and driving inequality.

"The acceptance of austerity that has taken over at Westminster, despite all the evidence of its failure, is one of the most persuasive cases for bringing full powers to the Scottish Parliament so we can deliver prosperity and equality, instead of having a Westminster government determined to punish the poor."

The SNP also highlighted a change to pension credit which could affect 100,000 Scots.

Osborne announced last week that the Government was ending the five-year "assessed income period" for the benefit, which was designed to avoid intrusive means-testing.

From 2016-17, pensioners will have to apply more regularly for the credit, raising fears that many will be put off from claiming, and so lose out.

The TUC has called it a "bizarre decision" which only makes sense in the context of saving the Treasury around £45 million a year.

SNP MSP Kevin Stewart said it was a "blatant cash-grab" by Westminster. He said: "The move will remove the certainty about how much money older people have coming in. It will increase the stress and hassle that older people face by requiring constant income assessments to access pension credit."

Osborne said that fairness was one of the three principles underpinning the spending round, alongside reform and growth. He told MPs the changes would "make sure we are all in it together by ensuring those with the broadest shoulders bear the largest burden".

A Westminster spokesman said it was not fair to compare the 2014-15 and 2015-16 forecasts, as the latter were more accurate than the former.

"The new analysis uses data to calculate a more accurate picture of the take-up of benefits. This means that the modelling now captures more accurately those affected by changes to taxes and benefits."