Schools could be forced to cut staff in order to pay the increased National Insurance contributions ann- ounced in this week's Budget.

Headteachers have condemned the decision by the Chancellor, Gordon Brown, to increase employers' contributions by one per cent. The increase, which will be introduced in a year's time, could cost some schools more than £25,000 a year -- the equivalent of paying for a full-time teacher.

Almost all schools are responsible for managing their own budgets -- a move which makes them employers in their own right. However, delegated funding also makes them responsible for paying employer's contributions.

Nicholas Young, the headteacher of Wheatley Park School, in Holton, said increased National Insurance contributions would hit school staffing.

He said the one per cent increase would cost his school £25,000 a year.

He said: "I fully support the increased funding for the health service but have concerns about the increase in employers' contributions.

"We are still not at the level of staffing and funding we had nine years ago. In 1993, I had 83 teachers and I have now got 78, despite having 50 extra pupils.

"This is a payroll tax that applies equally to hospitals, schools and old people's homes, as businesses. If we had to make cuts, the only thing we could take it from would be staffing.

"Gordon Brown is playing political games. Rather than putting income tax up, he is taking resources away from schools."

He added: "It is hard enough getting teachers anyway, and something that makes us have to work with even less teachers is very worrying. If he had increased income tax, we would be better off."

Clive Hallett, the secretary of the Oxfordshire branch of the National Association of Head- teachers, and the headteacher of Wheatley CofE Primary School, said: "It is appalling. Schools are going to foot the bill for employers' contributions. We will need more funding to pay for it, otherwise children will suffer."

Oxfordshire County Council education officer John Mitchell said: "It appears that this will be an additional burden, and schools will need to look at what this means for them."

The Department for Education and Skills declined to comment.