New doubts over whether Scots free child care extension funding will be adequate

And spending on childcare will double to £840 million a year by 2021-22 to help pay for it.

But there are worries that the money might not be enough to give all children what they are entitled to.

Organisations like the Fair Funding for Our Kids campaign have been concerned current levels of funding have not been enough to pay for children's present entitlement of offering all three-and four-year-olds 600 hours of funded nursery provision per year.

There has been worries that many children are currently missing out as many working parents cannot find nurseries which offer suitable hours - and that in some local authorities there are set numbers of places in private partnership nurseries.

In practice councils have used the funding to invest in their own nurseries irrespective of whether the places are suitable for working families who need all-day care.

Leading think tank Reform Scotland said two years ago that figures show a postcode lottery of unrestricted access to Government-funded pre-school early learning places as councils, who hold the purse strings, feel the pinch of budgetary constraints.

The free nursery education programme is paid for through a Government allocation to local authorities and is offered at council-accredited day nurseries, private nursery schools, pre-schools, playgroups and primary school reception classes.

In 2011,The Herald revealed East Dunbartonshire Council was the first local authority to limit funding because the £1.3m it allocated in its budget for funding partners' nursery places had run out.

It decided to refuse new funding requests for parental choice of private-sector nursery care after a July deadline and provide a local authority nursery. But at the time local authority nurseries did not provide the wrap-around care most working parents required.

Other councils have since admitted introducing restrictions, either by capping the number of places available, setting deadlines, or only accepting or prioritising local children.

Katherine Sangster of parents group Fair Funding for Our Kids said the increased funding was "welcomed" but there was "concern" over whether it was enough to ensure all children got their new entitlement and said it was important the money was ringfenced within local authority budgets.

Mrs Sangster: "We would welcome this, but we would ask the Scottish Government to look at the fact that one in three are currently not getting a fully funded place before they move to doubling this."

A March survey by The National Day Nurseries Association, which has been fighting without success to ensure that parental choice is enshrined in law in Scotland and that pre-school education funding follows the child directly, rather than going to councils, revealed that just half of nurseries in Scotland plan to offer 1140 free early learning and childcare hours when the Government’s policy comes in.

And fewer than 50 per cent of private and third sector nurseries say they will offer extended ‘free’ hours – meaning many families may not be able to access funded places.

Worries revealed in NDNA’s Annual Nursery Survey for Scotland were that the scheme will falter if hourly rates offered to private and third sector nurseries by local authorities for the ‘free’ provision are not enough to cover costs.

Purnima Tanuku, chief executive NDNA Scotland, said: “NDNA Scotland welcomes the principle of doubling the investment in childcare in order to double the free childcare entitlement for families by 2020.

“However, until we see more details about the hourly rate to providers, we won’t know if nurseries will be able to deliver this pledge sustainably. Will this increase in investment translate into a meaningful, sufficient rate for nurseries and other providers?

“For this promise to be delivered successfully, the sector needs to be consulted every step of the way and all types of provider fully on board to give parents true choice.

“The sector would like to be able to fulfil the Scottish Government’s ambition to pay staff the Scottish Living Wage, but this is just not possible on current funding rates paid to providers for 600 hours funded childcare per year.”

The Scottish Government said the move will ensure high-quality learning and care is available for all three and four year olds and eligible two year olds and is expected to save parents around £350 per child, per month.

It said it would "work closely" with local government this autumn to agree a multi-year funding package to deliver the expansion.

The First Minister said: "Our expansion of nursery education is truly transformational.

“Currently we deliver around 16 hours of early education and childcare a week – that’s already an expansion. But some parents still struggle to find and fund the childcare they need to allow them to work. We are going to change that."