Nukufetau is an atoll located within the nation of Tuvalu. The territory was historically claimed by the United States under the Guano Islands Act during the 19th century. It was eventually ceded to Tuvalu through a treaty of friendship concluded in 1979, which officially came into force in 1983.
The atoll has a population of 581 people who reside on Savave islet. While the provided subject description identifies it as a city in Niue, the source material specifies its location within Tuvalu and its status as an atoll.