People with disabilities now have another avenue to complain about being discriminated against under an agreement ratified by 40 nations.

Australia has signed up to the UN's Convention on the Rights of Persons with Disabilities Optional Protocol.

The protocol, agreed to by 40 nation's, allows complaints to be lodged to the UN if all domestic remedies have been exhausted.

Disability Discrimination Commissioner Graeme Innes said it was crucial to get a new national disability strategy up and running.