Gordon Brown's childcare strategy has failed to deliver affordable nursery places for millions of parents who are forced to rely on relatives to look after their children instead, a government study has found.

Despite the creation of half a million new nursery places and a pledge from Mr Brown of affordable childcare for all, the number of families turning to grandparents, aunts and even neighbours is on the increase.

The study, commissioned by the Department for Children, Schools and Families into how its own strategy is working, found that the percentage of families using formal childcare has fallen from 57 per cent to 54 per cent in the past three years.

It was conducted by academics at the National Centre for Social Research. It said: “The evidence suggests overall that the ten-year childcare strategy has not had as much impact as intended, particularly in relation to the most disadvantaged children.

“A substantial minority of parents still thought that affordability was fairly or very poor (36 per cent) and that there were not enough childcare places in their local area (37 per cent).

“Despite a small improvement in parents' views on the affordability of childcare, cost remains an important barrier to the use of childcare for some parents, especially large families and those with younger children.”

The drive to expand the number of affordable nursery places was driven by protests from mothers who said that the cost was stopping them going back to work. The Government was also moved to act by data showing that children from disadvantaged families particularly benefit from this type of structured childcare. Ministers were alarmed that bright children from poorer families were falling behind less able middle-class children from as young as three.

But the report suggests that formal childcare is still beyond the reach of many families. About two thirds (65 per cent) are using free “informal” care with nearly half (47 per cent) relying on grandparents for childcare, and 19 per cent using other relatives.

In terms of older children, only 17 per cent of parents are using the much-vaunted after-school clubs. This figure has not changed since 2004, despite the “extended school” initiative, which calls for wraparound care from 8am to 6pm at every school.

The study also said that parents struggled to find childcare during holidays and at weekends, with particular problems facing shift workers.

The Department for Children, Schools and Families, which commissioned the report, admitted that it was disappointed by the findings.

“We acknowledge that the take-up of childcare amongst lower income families is lower than among better-off families, which is why we spend £3.5 million a day on support for childcare through the Working Tax Credit,” a spokesman said.

There was better news on the take-up of the 12.5 hours of free childcare a week for three and four-year-olds offered by the Government. Separate figures found that virtually all four-year-olds and 95 per cent of three-year-olds were using their free entitlement to childcare.

In December 2004 Mr Brown, who was Chancellor at the time, promised “a ten-year childcare strategy” to help to create a “welfare state that is truly family-friendly for the first time in its history”.

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