A surge in the number of parents applying for free childcare in Norfolk has sparked fresh fears that providers won't be able to cope with demand.

Traditionally, parents were entitled to 570 hours of free childcare for three and four-year-olds - roughly 15 hours a week for the 38 in the school year - but last September it was doubled to 30 a week for eligible parents.

Childminders and nurseries have warned the funding they receive does not cover costs - with some saying they may be driven out of business or unable to offer the free hours, leaving a lack of places for parents.

New figures from the Department for Education show that in the summer term, 4,840 parents applied for a code to access the government funded hours - up 68pc on the autumn term.

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Once issued, parents must take a code to a provider to be validated. The figures show that 4,020 codes in Norfolk have been validated so far this summer - 820 fewer than the number issued.

It reflects the national picture - around the country, 327,000 codes have been validated, 50,000 fewer than issued.

Neil Leitch, chief executive of the Pre-School Learning Alliance, said: 'With 50,000 parents yet to have their codes validated, it's clear that the government is going to face a real challenge in ensuring the delivery of sufficient 30-hour places during the summer term.

'Given that most providers will have seen little or no change in funding rates this April despite significant increases in minimum wage requirement and other costs it would not be surprising if many were unwilling to consider increasing the number of 30-hour places they offer, meaning that many areas of the country are likely to see a shortage of available places.'

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In Suffolk, it is a similar picture. The amount of parents applying for a code has risen by 68pc, and, of the 4,469 codes issued, 1,028 are yet to be validated.

Children's minister Nadhim Zahawi said on Twitter said the provision was 'saving hardworking parents on their childcare bills and giving them extra cash in their pockets'.

In November, it was revealed that there had been a net loss of 1,146 nurseries from the Early Years Register around the country since the scheme was introduced.