Prime Minister Christopher Luxon's office has refused to release any documents — or even their titles — about advice he has received on "grey-zone operations," citing national security.

RNZ asked for the advice under the Official Information Act, the law that lets the public request information from the government. The response confirmed that several documents exist, but none would be released. RNZ

Grey-zone operations are hostile actions by countries that stop short of actual war. A spokesperson for the Prime Minister gave examples: sabotage of undersea cables and pipelines in the Baltic Sea, and ships being harassed in the Strait of Hormuz in a way that disrupts trade.

Luxon first talked about the grey-zone threat in a speech before the Budget. He listed it alongside cyber-attacks, disinformation, and pressure on supply chains as tools countries use against each other. RNZ

In June, the government announced one concrete response: a round-the-clock monitoring system for undersea telecommunications cables. If a ship gets too close to a cable, the system sends an alert and a warning.

The Official Information Act lets the government withhold information for national security reasons. Officials often do this when releasing documents could reveal what advice ministers have received, or where the gaps are. In this case, the government would not even confirm the titles of the documents. That means the public cannot see what questions were asked, which government agencies were involved, or when the advice was sought.

The bigger picture is that Luxon's choice to talk about grey-zone threats publicly is significant on its own. By grouping them with cyber-attacks and disinformation, he signalled that the government sees the range of threats as wider than traditional military ones. The cable monitoring system is the only actual measure made public so far.

The examples the spokesperson chose also tell us something. The Baltic Sea and the Strait of Hormuz are both places where New Zealand has no military presence, but where disruption affects the whole world's economy. That suggests the government is thinking about these threats globally, not just at home — even though the only response announced so far is for New Zealand's own waters.

We do not know what the advice to the Prime Minister actually says, which agencies gave it, or whether more measures are being considered. The refusal does not say whether any of this information might be released later.