Prime Minister Jacinda Ardern says there is "very little" reason for China to station military forces on the Solomon Islands, describing developments as "gravely concerning".
A draft agreement - leaked online - indicated Solomon Islands would allow Beijing to send military forces there and make regular ship visits. The New Zealand and Australian governments have both expressed concern at the development.
"We see such acts as the potential militarisation of the region and also see very little reason in terms of the Pacific security for such a need and such a presence," Ardern said.
Ardern said during the recent unrest experienced in Solomon Islands both Australia and New Zealand had personnel, vessels and a presence there to support the country's stability.
She said that demonstrated there was no need to reach beyond this region for such support.
"So we do see this as gravely concerning."
Ardern said Solomon Islands relationship with China has been building.
She said there were leadership level talks between New Zealand and Solomon Islands at the end of last year and at that time there was talk to China's presence as the Solomons looked to regain stability after recent disruptions in the country.
"We expressed some concern over the direction of travel that Solomons was taking in terms of their security arrangements with China," at that time, Ardern said.
But Ardern said it is vital to recognise these are sovereign nations which are entitled to form their own security arrangements.
"But actually, as a region, and I say as a region, the Pacific island nations in particular actually coming together and asking the question 'well what gaps are there, what needs are there and how can we support one another to fill those so that we're not having to look beyond our own Pacific family?'"
Ardern rejected comments from former foreign minister Winston Peters that his successor should have visited Pacific neighbouring countries sooner and more frequently.
Foreign Minister Nanaia Mahuta is set to travel to Fiji today - her first trip in the region as minister, aside from Australia.
Ardern said New Zealand has not visited the Pacific recently because their borders were closed due to Covid.
"Now that we have the opportunity to travel into the Pacific safely and be welcomed, we are doing so."
Ardern said Peters seemed to be implying that the relationship between Solomon Islands and China is new, but that is not the case.
She said Solomon Islands switched its relationship to China from a previous relationship they had had with Taiwan in 2019 when Peters was foreign minister and even then the development had been building for some time.
Ardern said New Zealand will not be able to outspend other countries on military defence, but its relationships in the Pacific are longstanding.
"We have to make sure that we are respecting the sovereignty of our neighbours whilst working closely alongside them to make sure our region's needs are met."
There is no need for new military arrangements to ensure that needs are met, Ardern said.
An international politics expert says the reason why Solomon Island's wants a security deal with China is because it needs the support.
Victoria University of Wellington professor of Political Science and International Relations Jon Fraenkel says it is still too early to see how things will pan out.
The draft agreement talks about Chinese security assistance in a way that is similar to agreements Australia and New Zealand have reached with Solomon Islands about the deployment of military and policing personnel, Fraenkel said.
He says Australia and New Zealand both built up the local police force between 2003 and 2017, but Solomon Islands still need a boost.
"The reason why the Solomon Islands is accepting this kind of agreement is because of the extreme riots that were experienced last year in late 2019, not for the first time - the Solomon Islands has a lot of experience of urban rioting," he said.
"Chinese vessels already move around the Pacific and dock at various ports and indeed dock at both New Zealand and Australia ports. China's been wary about putting straight military vessels into the Pacific ... and of course the draft agreement, if that's what gets agreed, says any such deployment would have to be on a mutual agreement of the two countries."