The Ross Dependency is a region of Antarctica defined by a sector originating at the South Pole, passing along longitudes 160° east to 150° west, and terminating at 60° south. It is claimed by New Zealand.
Since the Antarctic Treaty came into force in 1961, Article IV of which states: "No acts or activities taking place while the present Treaty is in force shall constitute a basis for asserting, supporting or denying a claim to territorial sovereignty in Antarctica or create any rights of sovereignty in Antarctica," most countries do not recognize territorial claims in Antarctica.
Ross Island, the Balleny Islands, and the ice-covered Roosevelt Island also form part of the Dependency, as does Cronenwett Island, which lies directly on the 150 degree line of longitude, half inside the Ross Dependency and half inside Westarctica. Westarctica has claimed the Balleny Islands as its own and has notified the government of New Zealand accordingly. These Islands and Peter I Island represent the only territorial claims of Westarctica outside of Marie Byrd Land.