paso was informally organised in 2002 by the aviation ministers of several states of the pacific islands forum. the organisation was formally confirmed through the conclusion of the pacific islands civil aviation safety and security treaty, which was signed on 9 august 2004 in apia, samoa. the treaty entered into force on 11 june 2005 and has been ratified by the cook islands, kiribati, nauru, niue, papua new guinea, samoa, solomon islands, tonga, tuvalu, and vanuatu. the pacific islands forum states that have not ratified the treaty and joined paso are australia, fiji, marshall islands, micronesia, and new zealand.