Patricia Lewsley also denounced what she dubbed the shocking “postcode lottery” in services for youngsters with autism and other learning difficulties.

Her claims came in the wake of a devastating UN report published on Friday, which said Britain was failing to meet standards on improving children’s rights.

In a document presenting more than 150 recommendations, the Geneva-based UN Committee on the Rights of the Child slammed ASBOs and the use of ultrasound devices to disperse youngsters.

Ms Lewsley has called for the Stormont Assembly to implement all the report’s recommendations.

She said it was vital to spend more on children’s mental health, review the use of police Taser guns on young people and focus on meeting the 2010 pledge to halve child poverty.

Ms Lewsley added: “There are 32,000 children in Northern Ireland living in deprivation and this will worsen as the economic crisis deepens.

“The Assembly must look at ways to protect the most vulnerable children in low-income families who are already suffering.

“We also have children languishing in jail on remand for far too long while awaiting trial and children vulnerable to ‘suicide websites’.

“There are also children in travelling communities living on sites without even basic provisions such as water for showers.”

The commissioner added that Northern Ireland spends the least on social protection per child in the UK.

“We spend only £287 per head on personal and social services for each child in Northern Ireland,” she said.

“This is compared to £402 per head in England, £513 in Scotland and £429 in Wales.”

Ms Lewsley admitted ministers had made a great deal of progress in implementing the UN Convention on Rights of the Child since 2002 – but stressed there was still a “long way to go”.

The UN report contains more than 120 recommendations, 50 more than the last report six years ago.

It said the UK should prohibit, as a matter of priority, all corporal punishment in the family, including smacking.

Ms Lewsley has been an ardent campaigner on this issue, even taking her battle to ban hitting in the home to court.

Another worry was the national DNA database, which keeps the records of children whether or not they have offended.

The document added that reality TV shows such as Supernanny infringe children’s dignity, invading their privacy and portraying them “in a terrible light”.

UN advisors also expressed concern about high levels of poverty, teenage imprisonment, public attitude to children and Britain’s failure to tell youngsters about their UN-guaranteed rights.

Ms Lewsley said: “Children who are in most need are not getting the right services at the right time. This means that children in need of mental health services, who are disabled, or who are suffering poverty, are discriminated against in Northern Ireland.”