The Asian group of nations at the United Nations has changed its name to the Asia-Pacific group.
The change this week comes ahead of Ban Ki-moon becoming the first UN secretary general to attend a Pacific Islands Forum summit in Auckland next week.
The 193-state United Nations has been divided into five regional groups since 1965 to negotiate responsibilities and elections to UN bodies.
Pacific island nations, starting with Fiji, started joining the Asia group from 1970 as they started to become independent.
With Fiji, Marshall Islands, Micronesia, Nauru, Palau, Papua New Guinea, Samoa, Solomon Islands, Tonga, Tuvalu and Vanuatu now in the group, they make up more than one fifth of the membership and started pressing for the name to change last year.
Diplomats say at China's insistence the group will be officially called Group of Asia and the Pacific Small Island Developing States.
But documents will be allowed to use the Asia-Pacific Group.
Fiji's UN ambassador, Peter Thomson, says the move shows Pacific states are wanting to play their full part and assume their rights and responsibilities.
The UN secretary general will attend the Pacific Islands Forum summit next week as part of a tour of the region.
He will also visit Australia, Solomon islands and Kiribati.