A head teacher has asked the Government to step in to stop his pupils facing more lessons in mobile classrooms.

The number of students at The Causeway School in Eastbourne is set to double by 2004, but cash is not available to complete the buildings planned for them.

Between seven and 11 temporary classrooms will be needed just to house the extra intake next year.

Head Peter Barton has called this contingency plan "a total waste of money" and "totally unacceptable". He has written to Education Secretary David Blunkett in protest.

The Causeway School shares a site with Hazel Court School, which takes children with severe learning difficulties.

It opened in September 1998 and phase one of the building has been completed.

But cash-strapped East Sussex County Council is expected to agree a year's delay in the completion of the school when it sets its budget on February 20.

This would probably mean the project will not be finished until autumn 2003.

In his letter to Mr Blunkett, Mr Barton said: "This difficult situation is made all the more bizarre by the fact that every Eastbourne secondary school is bursting at the seams. By the middle of this decade, if growth continues, it is likely that another secondary school will be needed."

There are 444 students at Causeway now. By 2004-5 it is anticipated there will be 950.

Mr Barton said the school would have to rely on "significant temporary accommodation" from 2002.

He said: "In a new school with planned, phased development this situation is totally unacceptable."

Jay Kramer, lead East Sussex education councillor, said: "The temporary classrooms will be there on a temporary basis. It will be time-limited for a year."

Eastbourne Tory MP Nigel Waterson called the situation "appalling" and has also written to David Blunkett.