Parents groups have hit out after it emerged that £140 million of funding for childcare was not spent on nursery provision, according to a Scottish Government report.
Ministers have provided additional funding of £329 million over the last three year to councils to help increase free childcare cover to 600 hours a year, about three hours a day in term-time. But only £189 million of this was spend on childcare, according to a Scottish Government review of funding for the policy.
The claims prompted an angry response from local councils body Cosla which said they were "misleading."
It comes as the Scottish Government is planning to almost double the current provision to 1150 hours which would mean free nursery cover effectively covers the current school year.
The "transformational" plans are aimed at getting a generation of mothers back into the workplace and have been welcomed across the political spectrum. But parents groups have questioned whether it can be delivered, warning the current set-up prevents many from getting their existing entitlement.
Carolyn Lochhead of the fair Funding for Our Kids said: "You might have a place between 9am and ten past twelve - you can't pay to have your child there between nine o'clock and you can't pay to have them there after the sessions ends.
"For most parents that's completely unusable. So it's very frustrating to hear that there's funds available that maybe haven't been spent."
Ministers are now to examine the prospect of a "child account" system which would see funding follow each youngster throughout their childcare journey. The proposals will be at the heart of a new blueprint on childcare being published next week by ministers.
Childcare minister Mark MacDonald said it would be for councils to account for the apparent £140 million in spending in a Holyrood debate today, but he has has discussions with councils on the issue.
But he said: "It is clear that the Scottish Government has met its commitment to fully fund this policy."
But a Cosla spokesman played down the figures in the review.
He said: "We are very concerned that there are parts of this report that paint a very misleading picture and do not reflect the reality of what is happening on the ground. This is a crude assessment and it would be extremely unhelpful if this becomes the focus and detracts from the overriding success story that councils have delivered 600 hours.”
About 125,000 Scots youngsters between the ages of two and four currently benefit from the free entitlement childcare of 600 hours.
The Government is to undertake a consultation for early learning and childcare next week which will inform the Government's approach to implementing the 1150 hours pledge.
"We have a historic opportunity to create provision which gives our children's educational and economic prospects a sold foundation for success," McDonald said.
The minister said he is committed to delivering the "flexibility and choice" that is needed in the system, with trials to be launched early next year aimed at finding best practice in local delivery."