The health minister said it would cost almost one million pounds to expand the service provision available for detecting problems at the early stages of a child's education, on 23 April 2012.
Edwin Poots was responding to a UUP motion calling for multi-agency support teams to be available for every child.
He said he fully supported the multi-agency principle as it provided an early detection for children showing signs of difficulty.
"Multi-agency support teams, or multi-disciplinary teams as they are more commonly known, are exceptionally important in the early identification of difficulties which children are encountering with their development, or a problem which may prevent them achieving their full potential," he said.
He added that not all schools had this extra provision as they simply had not signed up to the scheme.
The minister said there were plans in place to ensure the service was optimised and used effectively.
He said it would cost £900,000 annually for the scheme to be made available in all schools, £500,000 of which would apply to the Northern Trust.
Mr Poots added that the pace of inclusion of all schools would be dependant on available resources.
The motion was carried on an oral vote.
The first part of the debate can be viewed