Niuean Premier Dalton Tagelagi says Covid-19 cases on his island nation are now "stable" after a flight from New Zealand sparked its first outbreak in the pandemic.

Tagelagi today met with Prime Minister Jacinda Ardern, Foreign Minister Nanaia Mahuta and Pacific Peoples Minister Aupito William Sio in Wellington.

It is Tagelagi's first official bilateral overseas visit since becoming Premier in June 2020.

The island nation, which relies heavily on tourism, has remained shut off through the pandemic until opening up to flights from New Zealand last month, which sparked its first Covid-19 outbreak.

Five people on the flight tested positive on day one, with one passenger hospitalised. Tagelagi was one of several close contacts who needed to isolate.

Premier of Niue Dalton Tagelagi and New Zealand Prime Minister Jacinda Ardern at Parliament today. Photo / Getty Images

Asked about the recent outbreak in Niue, Tagelagi said it was now stable.

It was the fourth week since opening and things settled down. There were five active cases and 23 in total.

Tagelagi said Covid was the "new norm" and they could not remain closed off forever.

Niue is a tiny South Pacific island nation situated between Tonga, Samoa and Cook Islands. Its land area is 260sq km and population about 1700.

It is part of New Zealand's realm, meaning Niue's citizens are New Zealand citizens and the Government assists with a range of economic, administrative and diplomatic affairs.

Tagelagi and Ardern today signed a renewed partnership agreement between the nations.

Despite the small mainland population, at last census counts, 30,867 ethnic Niueans were resident in New Zealand in 2018, and 4958 in Australia in 2016.

"With 30,000 Niueans living in New Zealand our whakapapa connections as well as our special constitutional links makes Niue one of Aotearoa New Zealand's closest partners," Ardern said ahead of the visit.

"Our ties have deepened in recent years while Niue's borders have been closed due to Covid-19.

"Niue has one of the highest levels of vaccination in the world and we have worked closely with them to achieve that, as well as offering economic support while tourism has been shut."

Refreshing the Statement of Partnership between Niue and Aotearoa New Zealand reflected deep cooperation on priority areas such as climate change, economic resilience and improved prosperity and the preservation of Niue's culture and language, Ardern said.

The statement also highlights areas of renewed cooperation arising from the pandemic, notably support for the health response and Niue's economic recovery, she said.

The meetings also offered the opportunity to further discuss the recent Pacific Islands Forum in Fiji, which focused on unity among Pacific nations particularly around security issues and climate change.

Tagelagi said Niue's priorities were in the oceans. But climate change was the biggest "single threat".

On the Pacific Islands Forum and unity issues with Kiribati splitting, Ardern said on the final day the Kiribati President had re-engaged.

The door remained open but it was up to Kiribati, she said.

On climate change issues at the Forum and criticism around Australia's ongoing coal and gas extraction, Tagelagi said he was still supportive of the new Australian government's change in direction.