The tiny South Pacific territory of Tokelau has failed to pass a motion for self-government, in the second referendum on the issue in two years.
Some 446 of the 692 registered voters supported an end to rule from New Zealand, falling just short of the required two-thirds majority.
Wellington has governed Tokelau since 1926, and gives it substantial aid.
Prime Minister Helen Clark said the islands were assured New Zealand's "ongoing friendship and support".
"It is for the people of Tokelau to decide both the direction and the pace of their political development," she said.
"Now the voters of Tokelau have signalled again, albeit narrowly, that they do not want such a change at this time."
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The vote follows a similar referendum in February last year, where the self-government proposal also failed by a narrow margin.
Wellington's ministers are said to be keen to comply with the United Nations, which has listed Tokelau as a territory to be decolonised.
Correspondents say the vote might have been swayed by about 7,000 Tokelauans who live in New Zealand - most of whom are said to oppose self-rule.
Tokelau is made up of three coral atolls which have no airport, roads or capital and are home to 1,500 people.
Tokelau's territory is just 4.7 sq miles (12 sq km), lying halfway between Hawaii and New Zealand.
Seized by Britain in 1889, the tiny islands were handed to New Zealand to administer in 1926.