A LEADING think tank has cast doubt on the SNP's flagship plans for universal free childcare after independence.

The Institute for Fiscal Studies said there was little evidence that a major expansion of free nursery provision would encourage tens of thousands of women to get jobs, as the Scottish Government claims. Director Paul Johnson said: "It may have a good effect on labour supply but the evidence for this is remarkably poor.

"I would not expect the additional X-millions spent on childcare to pay for itself in any sense in terms of additional tax revenue."

In its blueprint for independence, the White Paper Scotland's Future, the Scottish Government says all children from one to school age will be entitled to 1140 hours - equivalent to primary school hours - of free care per year by 2024. Ministers claim the policy will be paid for by more people, especially women, entering work and creating extra tax revenues.

Mr Johnson raised his concerns in a David Hume Institute seminar at Holyrood and while giving evidence to the parliament's economy committee.

He said he "took issue with the consensus" in favour of expanding free childcare, which is shared among all the main parties.

Scottish Labour has called on SNP ministers to speed up its planned expansion of childcare, arguing they do not need the powers of independence. The Coalition Government, driven by the Lib Dems, has expanded childcare south of the Border. Labour has backed further provision.

The IFS complained recently of a lack of clarity over the policy's aims and a shortage of evidence about parents taking jobs.

The report said: "The case for further extending universal provision of early childhood education and care is in fact not as easy to make as would seem to be implied by the growing consensus in this area."

A Scottish Government spokesman said: "Parents in the UK face some of the highest childcare costs in Europe and we will secure a wide range of benefits for children and their families by increasing funded provision.

"Building on the widely-welcomed increase in provision this August, Scotland's Future outlines the Scottish Government's proposals to use the powers and resources of independence to deliver a transformation in childcare on a phased, manageable and sustainable basis."