Definitions of "Southeast Asia" vary, but most definitions include the area represented by the countries (sovereign states and dependent territories) listed below. All of the states except for East Timor are members of the Association of Southeast Asian Nations (ASEAN). The area, together with part of South Asia, was widely known as the East Indies or simply the Indies until the 20th century. Christmas Island and the Cocos (Keeling) Islands[citation needed] are considered part of Southeast Asia though they are governed by Australia.[citation needed] Sovereignty issues exist over some territories in the South China Sea. Papua New Guinea has stated that it might join ASEAN, and is currently an observer.