Oxfordshire's new education chief Janet Tomlinson has delivered a damning verdict on the county's under-performing state schools.

Ms Tomlinson, Oxfordshire's director of children, young people and families, claimed children had a better chance of getting good GCSE results in Slough than Oxfordshire.

She blamed complacency in secondary schools for the failure to bring about improvements, promising new measures at schools deemed to be "coasting".

She said: "In general, children in Slough now have a higher chance of getting good GCSEs than children in Oxfordshire in terms of educational achievement.

"Oxfordshire schools should be doing much better. Nothing can mask that."

She said while test results in the county were at the national average, Oxfordshire was at the bottom when compared to similarly affluent counties.

Ms Tomlinson said some headteachers were "in denial" about their performance and said she would be bringing in heads with impressive track records.

She said: "We hope to recruit head teachers who have successfully turned schools around.

"There's already been a refreshing number of new head teachers who have come within the authority bringing new ideas."

Ms Tomlinson, who took up the post last summer, having been previously based in Slough, promised "decisive early intervention" if schools were in danger of failing - and not just for those facing special measures.

Specialist subject teachers and advisors would be sent to those schools.

She plans to revamp the county school improvement service with new experts, while heads and teachers would be encouraged to visit successful schools outside the area.

This year's figures for Oxfordshire showed 57 per cent of 15-year-old pupils achieved five GCSEs at grade C or higher, up on 56.3 per cent in 2006.

This was still well behind schools in Buckinghamshire, where nearly 69.2 per cent reached the benchmark, and Slough, an immigration hotspot where English is the second language for many, which still managed 63.7 per cent. The county also trailed Gloucestershire on 64 per cent and Cambridgeshire on 60.6 per cent.

Ms Tomlinson dismissed the idea that the poor results were due to a large number of private schools in the county, and said other affluent counties had similar numbers of such schools but still performed much better.

Chris Harris, headteacher of Larkmead School, in Abingdon, said: "The director is right. There's no argument. Heads in Oxfordshire recognise the rate of progress in Oxfordshire next to similar authorities is not good and needs to be better.

"But improvements only come through a solid base and it can take up to five years before you notice any difference. The main drive must come from individual schools who will bring up the whole county."