The promised legislation would be a "specific Commonwealth torture offence" that would operate alongside existing offences in both State and Territory criminal laws. 

A-G Robert McClelland today announced the plans as part of a more general offensive against torture. 

The Government on Tuesday signed the United Nations Optional Protocol to the Convention Against Torture at the UN Headquarters in New York.

The Optional Protocol represents a further prevention and enforcement mechanism by obliging parties to allow periodic international inspections of its places of detention, and to establish formal mechanisms to enable regular examination of the treatment of persons in places of detention.

Currently in Australia, there is no single, comprehensive offence that criminalises torture.

McClelland said the measures send a strong message both within Australia and internationally that the government will take all necessary steps to eliminate the use of torture.