A high-profile report published today calls for 50 hours of childcare per week to be available for all children in Scotland up to the age of 12.

However, TESS can reveal that the Commission for Childcare Reform’s proposal would cost Scotland’s largest council £169 million a year - more than three times its current early years budget. The figure was calculated by Kenny Forsyth, a member of the commission.

Currently Glasgow spends £53 million a year on the early years and has a total education budget of £450 million. Maureen McKenna, Glasgow’s director of education, said that finding £169 million was “unrealistic given the current finances”.

The commission today delivered a letter to first minister Nicola Sturgeon and David Mundell, secretary of state for Scotland, urging radical action to transform childcare in Scotland. Current provision was “incoherent and piecemeal”, said Jackie Brock, chief executive of Children in Scotland, the lead organisation involved in establishing the commission.

Expanding free hours for three- and four-year-olds should not be the Scottish government’s “first priority”, according to the commission’s report. It argues that the focus should rather be on “smoothing cost burdens” for all families, especially those living in poverty.

Existing plans to increase free nursery hours to 30 per week by 2020 would result in Glasgow having to double its nursery places from 5,500 to 11,000, said Ms McKenna.

She added: “We need to take a step back and look at what we are delivering from 0-8 years. If all four-year-olds are in full-time [childcare] we will need to change what we do in P1 to ensure that their learning is effectively built upon.”

Another leading education chief said that the school starting age should be back on the table if the Scottish government wanted to continue expanding subsidised childcare.

John Fyffe, the president of directors’ body ADES and director of education and children’s services in Perth and Kinross, wrote to education secretary Angela Constance asking: “Where does nursery provision end and formal schooling begin?”

By 2020 children will spend more time in nursery than school, given that the school week lasts just 25 hours.

Mr Fyffe called for “a national conversation” about what happened during the early years, echoing Ms McKenna’s comments that a child’s journey through the early years needed to be re-examined.