The Human Rights Council of Australia has asked the UN's Commission on Human Rights in Geneva to investigate the holding of children in immigration detention on Nauru.
Its spokesman Howard Glenn says the payment of another country to take detainees and hold them outside one's own law and obligations is a practice which deserves serious attention by the UN.
Mr Glenn has told a hearing in Geneva that six Afghan children remain in detention on Nauru after being picked up the Australian navy in 2001.
He says the agencies in charge of looking at Australia's treatment of these and other asylum seekers have proven ineffective against the abuses.
Mr Glenn says the UN working group on arbitrary detention was not able to visit Nauru and, apart from an early visit by Amnesty International in 2002, human rights organisations and media are kept off the island through a simple process of denial of visas.