The SNP must use new powers being handed to the Scottish parliament to help the country's poorest or risk being seen to "go along" with Tory cuts, Gordon Brown has said.
The former prime minister, who was one of the leading figures in the campaign to keep Scotland in the United Kingdom last year, said the SNP has "reluctantly" had to accept that it will be able to top up tax credits cut by the UK government when the new powers, outlined in the Scotland bill, are devolved.
Brown was speaking at a Child Poverty Action Group event where he blasted George Osborne's tax credit cuts, warning they could plunge millions of children and working people into poverty across the UK, and he urged the SNP-led Scottish government to take action.
"The powers that have been granted to the Scottish parliament are powers that enable the Scottish parliament to top up any welfare benefit," said Brown. "The Scottish National party have reluctantly had to accept that, and they will now have the choice as to whether they use these powers to make Scotland a fairer place or whether they go along with Conservative policies."
There was confusion last week over whether the Scottish parliament would have the power to top up cut tax credits under the proposals in the Scotland bill, which was passed in the House of Commons on Monday.
Scottish Labour said Holyrood would have the power to top up tax credits and laid out a plan to do so, whereas the SNP initially said it would not have that power, before making an apparent u-turn when the issue was debated in parliament and going on to say it would lay out a "properly costed" plan soon.
Brown said he expects Scottish voters in next May's Holyrood election to "reject" the tax credit reforms, and said they will demand the government use Holyrood's new powers to change Scotland's welfare system for the better over the course of the next Scottish parliament.
"There is a chance that over the next few years that Scotland will have a different social model from that of the rest of the United Kingdom," he said. "That will be a pressure on the rest of the United Kingdom, but it will also be a pressure on those people in government in Scotland.
"I can see a situation where, even if the tax credit proposals go ahead in England ... these tax credit proposals will be rejected in their entirety by the Scottish electorate when they vote next May."