A court ruling that denies parents the right to seek a school outwith their local area for children with additional needs will be overturned, First Minister Alex Salmond promised yesterday.

He gave a categorical assurance in the chamber at Holyrood that "whatever steps necessary" will be taken to ensure that families with vulnerable children who need extra help will have a free choice of school. If an appeal on the case to the House of Lords was not successful the First Minister said his government would alter the legislation.

The Herald this week highlighted a Court of Session ruling that a mother in West Dunbartonshire whose son is blind and has cerebral palsy did not have the right to make a school placing request to another local authority.

The ruling outraged campaigners who saw it as discriminatory since it applies solely to children who require additional support because they are covered by the specific legislation Lord Macphail was ruling on, the Education (Additional Support for Learning) (Scotland) Act 2004.

An estimated 25,000 children in Scotland are classed has having additional needs for reasons that range from autism to bullying to family bereavement.

At First Minister's Questions at Holyrood, Mr Salmond told Liberal Democrat education spokesman Jeremy Purvis: "It is the intention of the Scottish Government to ensure that the parents of children with additional support needs are able to make placement requests to schools outwith their local authority area."

Mr Purvis asked whether the First Minister will look at reforming the 2004 legislation if an appeal of the decision to the House of Lords fails.

The SNP leader said it would. "We will take whatever steps are necessary to ensure that parents of children with additional support needs are able to make placement requests to schools outwith their local authority area," he added.

Mr Purvis said: "If the appeal to the House of Lords fails, I will hold the First Minister to his promise to amend the legislation in the Scottish Parliament and close this legal loophole."

The landmark case involved Wilma Donnelly, from Balloch, who has been trying for more than a year to move her son Mark, 16, from Dumbarton Academy to to Ashcraig School in Glasgow, a specialist secondary catering for pupils with physical or visual impairment.

Her lawyers argued that the reference in law to making a placing request "to an education authority" applied to any local authority, but Lord Macphail ruled that this meant an applicant's own local authority.

Her solicitor, Iain Nisbet of Govan Law Centre, plans to appeal against that interpretation to the House of Lords.