It's likely to be a free and frank discussion when Foreign Minister Murray McCully meets with representatives from Nauru's government later today.
The New Zealand Government announced last week that it was suspending the $1.2 million (US$750,000) of aid it provides to keep Nauru's justice sector going.
The decision followed growing concerns about the deterioration of the rule of law in the tiny Pacific nation and worries about democratic and civil rights.
It's anticipated McCully will have formal talks with Nauru at some point today on the sidelines of the Pacific Islands Forum in Port Moresby.
Ahead of that meeting, Prime Minister John Key said New Zealand's message to Nauru is “really clear”.
He pointed to concerns about Australian judges being asked to leave Nauru, as well as the seizure of opposition MP Roland Kun's passport when he is not facing charges.
“We fund that situation, that situation's unacceptable to us and if we were to carry on funding it, I think you would look at us and think that's rather odd,” Key told reporters.
Key didn't think New Zealand's relationship with Nauru had become tense, instead saying that it was “free and frank”.
Nauru's Justice Minister David Adeang has previously accused New Zealand of trying to undermine his country's sovereignty.
New Zealand's other aid to Nauru, which amounts to about AUD$1m, is not under threat.