Children at 27 schools in Brighton and Hove are being taught in temporary classrooms.

The figure is higher than in many large urban areas, including Manchester, which has 23, and Liverpool with 25.

The Department for Education, which published the statistics, said temporary classrooms were not a suitable long-term option and should be replaced.

In East Sussex, 96 state-run schools still had temporary classrooms. In West Sussex, the figure was 170, among the highest in England.

Many of the makeshift buildings being used date back to the Sixties and Seventies.

They were considered a fast and cheap solution to spiralling school populations following the post-war baby boom but were not intended for decades of service.

Education minister David Miliband said he did not want to see children being taught in them, even on a medium-term basis. But he did not blame local education bosses and admitted some headmasters had no choice.

Mr Miliband said: "The department does not encourage the replacement of defective permanent accommodation with temporary mobile classroom accommodation. But we do accept the necessity, in some cases, to respond to short-term need or emergencies."

Although many local education authorities are in a similar position, some do not have any temporary classrooms.

Details of temporary building use comes in the wake of a pledge by Chancellor Gordon Brown to revamp schools.

In last month's Budget, he said: "I can announce that to advance modernisation plans, the overall capital investment budget for English education, which was £1 billion a year in 1997, will be £6 billion next year rising to £8.1 billion a year by 2008.

"Our capital investment allocations will ensure for every constituency in the country that by 2015 every secondary school can be refurbished or rebuilt with world-class technology in every school and the best state-of-the-art learning support in every classroom."

David Hawker, director of children, families and schools at Brighton and Hove City Council, said: "We have pledged in our asset management plan to replace all pre-1980 hutted classrooms by 2007.

"This year we will be removing four temporary classrooms at Hangleton Junior School and have just completed work at Saltdean Primary that has taken away triple hut classrooms.

"In the financial year 2004/05 we will be starting work at West Hove Junior School to remove four temporary classrooms and undertaking renovation at Somerhill Junior that will not only remove the temporary accommodation, but also improve the teaching space throughout the school.

"We know we have a major job on our hands and it will take time to complete, but we are determined to improve teaching facilities at all our schools. Funding is scarce so we are allocating resources to where there is most need first."