The SNP has been criticised by the country’s public spending watchdog for failing to work out the cost of implementing newly devolved benefits systems.
In a report to be published tomorrow, Audit Scotland said ministers should publish the projected costs of the new Scotland Act powers, a warning it also issued to the SNP last year.
The UK Government has already handed Holyrood £200 million to bring in the new social security powers.
But auditors said it will cost “much more than £200 million to implement all these powers”, and that additional costs would have to come from the overall Scottish budget.
The organisation said more transparency was required from the SNP, and warned “significant” work would be required to get all systems ready to deliver the new powers, particularly in IT.
Implementing new social security powers would be “hugely complex”, the report added, and more work is needed to ensure sufficiently skilled staff are in place to deliver these.
There was also a warning that it would be “challenging” to ensure enough workers would be found in time.
The Scottish Government has already spent £62 million implementing new powers, and ministers themselves estimate the new social security powers alone will cost £308 million over the next four years.
Audit Scotland added: “The way the Scottish economy performs relative to the rest of the UK will have a greater influence on public finances than ever before.”
Scottish Conservative shadow social security secretary Adam Tomkins said:
“In short, the SNP simply hasn’t done its homework when it comes to the huge challenge of implementing these significant new powers that are coming to Holyrood.
“The nationalists are about to learn not only how difficult it is to achieve a fair welfare system that’s affordable and sustainable, but how complex it is to get it up and running.
“It’s incredible that the SNP government hasn’t at least attempted to work out how much this is going to cost.
“If ministers are caught out by these costs, the excess cash will have to come from the budget, and that will mean schools, hospitals and other public services being short-changed.
“Time is running out, and the people of Scotland will not forgive the SNP government if it makes a mess of the processing of this.
“We’ve seen what a farce the SNP managed to make with processing CAP payments for farmers in recent years.
“If that’s repeated with social security money, the chaos will be unprecedented.”