Boys should be allowed to wear skirts to school to avoid "serious distress" caused by gender-specific uniforms, a children's tsar has argued.

Tam Baillie, Scotland's commissioner for children and young people, suggested forcing children to wear such skirts or trousers depending on their gender could contravene laws set out by the UN Convention on children's rights.

Baillie's announcement was prompted as he stepped in to defend 13-year-old Luca Scarabello, from Falkirk.

The teenager is the latest schoolboy to raise the issue of boys wearing trousers to school, after Chris Whitehead was nominated for a human rights award after wearing a skirt to school.

But rather then proposing a blanket ban, Baillie proposed a flexible approach and encouraged further debate on the issue.

"I would agree gender specific uniforms or dress codes can cause serious distress in gender-variant pupils. School uniforms and dress codes should not discriminate directly or indirectly against any of these protected groups.

"Schools should review their uniform code policies to ensure they do not have the effect of unlawfully discriminating against pupils witha protected characteristic."

But Norman Wells, of the Family Education Trust, told the Daily Telegraph: "This is yet another case of the language of children's rights being used in an attempy to add weight to what is nothing more than a personal minority view."

The Convention of the Rights of the Child was established in 1989 and sets out human rights for children in 54 articles.

Article 2 (non-discrimination) states: "It doesn't matter whether they are boys or girls...no child should be treated unfairly on any basis" while Article 3 (best interests of the child) says: "The best interests of children must be the primary concern in making decisions that may affect them. This particularly applies to budget, policy and law makers."

The protection of rights of children is laid out in Article 4: "Governments have a responsibility to take all available measures to make sure children's rights are respected, protected and fulfilled."

All three articles could be used in Baillie's argument to ban gender-specific uniforms.