British parents forced to pull 'sick days' to look after children during the school summer holidays cost the economy £100m a year, new research reveals.

Last year one in six mums and dads called in sick to care for children during the summer break, unable to afford the rising costs of holiday childcare and entertainment such as holiday clubs and play schemes.

The study by The Family and Childcare Trust and Netmums also found that families in the UK are likely to spend more than £100 per child every week during the six-week break, suggesting holiday childcare is becoming increasingly expensive.

The average cost of one week's full time (50 hours) childcare in Britain – including holiday clubs – now stands at £114.51, which is 1.7% more expensive than last year.

One in four of the 1,500 parents questioned said they had been forced to cut their working hours during the school holidays and one in eight said they have given up jobs altogether because they could not find affordable childcare.

The findings also show that families face different costs depending on where they live. In England alone, full-time holiday childcare costs around £116.18 a week on average. Prices are higher in the South East, reaching £140.88 on average.

Families in the North West have the lowest weekly holiday childcare costs at £103.38.

Trust chief executive Anand Shukla told Associated Press: "A combination of unaffordable prices, lack of holiday childcare and inflexible employers is not only causing stress for parents, but it's bad for the economy.

"Most parents have no choice but to work and should not have to take sick days to manage childcare. This is not the way to operate a modern economy."

Shadow childcare minister Lucy Powell said: "Under David Cameron childcare costs are soaring and the availability of childcare is plummeting, causing a summer of misery for many parents trying to balance work and family life in the holidays."