Governors and education pressure groups say the removal of limits will lead to more overcrowding and bigger classes. Labour is pushing for a Commons debate on the issue and says it is aimed at lowering standards to pave the way for the nursery voucher scheme.
The Government wants to reduce the "regulatory burden" on schools by abolishing minimum space requirements. Simon Goodenough of the National Governors' Council said: "It will inevitably open the way to more pupils being squeezed into classrooms. Schools are trying to do the best with the resources they have."
Margaret Tulloch of the Campaign for the Advancement of State Education said: "This will undermine the argument that schools can use to show they are overcrowded."
Meanwhile, evidence of rising class sizes continues to emerge, particularly in primary schools. Figures produced by the Department for Education and Employment and included in the recent report of the School Teachers' Review Body on pay, show that class sizes in primary and secondary schools have risen by 7.6 per cent since 1988.
Under the 1981 regulations, primary schools have to provide 2.61 square metres for each pupil under the age of nine. Secondary schools must provide 4. 69 square metres for over-15s and a little less for younger pupils.
The Government argues that governors and local education authorities will still be able to set overall admission numbers for schools but abolishing the limits will give them greater flexibility in managing their facilities.
Guidelines, rather than regulations, will be produced to give LEAs and schools "benchmarks" on floor space and play areas.
Regulations covering the playing field space per pupil are to be retained because, schools minister Robin Squire said in a written answer last year, the Government believes schools and local authorities may be tempted to sell playing fields. But "that temptation does not arise in the same way in the case of teaching accommodation or recreation areas."
Cheryl Gillan, an education junior minister, has admitted that only two LEAs - Wandsworth and East Sussex - had supported deregulation, which Labour's David Blunkett said was intended to avoid investment in new facilities to cope with 86,000 extra pupils in the coming year. It would also boost the new nursery voucher scheme.
"Any operator would be able to get away with a bare minimum of space for nursery classes," he said. "It is an attack on the quality of what youngsters will get."