Prime Minister John Key says New Zealand could not follow suit if Australia moves to strip a New Zealand-Australian woman of citizenship to prevent her returning from Syria.
Mr Key was commenting on the case of a woman reported to be trying to negotiate a return from Syria to her hometown of Sydney in return for passing on information to Australia about Isis (Islamic State) terrorist networks.
Australia has taken a hard line on such cases and Prime Minister Tony Abbott is expected to move within days to change the law so dual nationals can be stripped of Australian citizenship if they were involved in terrorism - something he announced he intended to do earlier this year.
Mr Key said if Australia did take that action and stripped the woman of citizenship New Zealand was unlikely to follow suit.
"Obviously that's not our preference but we can't stop what Australia chooses to do. We can only reflect on whether we believe it is appropriate to leave a New Zealand citizen in a stateless position and I think the view we've taken is we don't support that."
He said New Zealand authorities were in contact with Australia but as yet had no information about the woman and did not know her name.
Mr Key said there was a question about whether the law should be expanded and that could be considered as part of the major review of security legislation now under way. However, he doubted New Zealand would go so far as to strip citizenship. It would be difficult to get enough support to pass such a measure.
"Secondly, it raises the issue of leaving people stateless, so I think it's unlikely. I just think that ultimate step of removing someone's citizenship is very unlikely."
It was likely the Terrorism Suppression Act would apply if such a person returned to New Zealand - the law covers those involved in terrorist activities. The foreign fighters legislation passed in New Zealand last year provided for matters such as passport confiscation for up to three years to stop people travelling overseas to fight for Isis and gave spy agencies greater powers to conduct surveillance without warrants on suspected terrorists.
The woman's case comes amid news that Isis militants have executed at least 400 people, mostly women and children, in the ancient Syrian city of Palmyra.
Eyewitnesses reported that the streets were strewn with bodies. It followed the killing of nearly 300 pro-government troops two days after they captured the city.
Isis has also strengthened its position in neighbouring Iraq with jihadi fighters killing more than 500 people when they captured the city of Ramadi last week.
The terrorist fighters are now just over 100km from Camp Taji, where New Zealand troops are deployed to help train the Iraqi Army.