Nipsa members have been taking industrial action

That is one of the contingency plans by the education boards in the event of a further strike by Nipsa.

Last month, a 10-day strike by classroom assistants shut more than half of special schools.

The union which has been on strike, Nipsa, has informed the education boards that it intends to hold another stoppage on or after next Monday.

Meanwhile, Seamus Searson, NASUWT, said all five teacher unions will take industrial action if unqualified and unchecked adults are allowed to work in schools.

All the unions are writing to their members telling them to meet school principals and tell them they will not co-operate with such measures.

BBC Northern Ireland education correspondent Maggie Taggart said: "Education boards have promised that no special schools will be closed in the event of a new strike by Nipsa classroom assistants.

"To get more children with special needs into schools, they have introduced contingency plans. One of them would allow parents to take care of their own child, but not deal with any others."

'Vulnerable'

Helen McClenaghan, chief executive of the Southern Education Board, speaking for all five boards, said: "The focus must be on children and young people and particularly the most vulnerable children.

"Contingency arrangements are only necessary if Nipsa pursues its indefensible stand."

She urged the union to ballot its members again. She said, under the contingency plans, parents would only be responsible for their own children.

But Bumper Graham of Nipsa said the employers' proposals were "ill thought-out".

"We are the largest union by far in this dispute... the issue is that there is a dispute, there is only one way to resolve this and that is meaningful engagement."

On Monday, Finance Minister Peter Robinson hinted that the Department of Education may need extra money to settle the classroom assistants' dispute.

In response to a question from Sammy Wilson, DUP, Mr Robinson said the department had "identified potential pressure" since the classroom assistants' dispute had not been resolved.

The GMB union also revealed that its classroom assistant members had voted four to one in favour of the offer from the employers.

It said it had the biggest response ever to any ballot.

Nipsa is the only union, so far, to have taken industrial action in this dispute over pay and conditions.