Christopher Luxon used his final hours in Tokyo to announce with Japan's Prime Minister a deal had finally been struck to share top secret information.
The agreement has been more than two years in the making and is like other agreements Japan has - or is pursuing - with Five Eyes partners to bolster its intelligence against China.
Prime Minister Luxon met Japan's PM at his residence in Tokyo with all the fanfare on Wednesday (local time) before getting down the business.
The two leaders weren't beating around the bush - times are tense
"We agreed and put forward a statement to further strengthen cooperation in broad areas including security and economy," Japan Prime Minister Fumio Kishida said.
Luxon said the pair talked about "the importance of our work together to deter North Korea from advancing its nuclear weapons and ballistic missiles programme".
Severe situations call for security. Kishida and Luxon announced a deal to share top secret intel has finally been struck.
The two leaders met as Russia's Vladimir Putin met with Kim Jong Un in North Korea just across the sea.
"We've concluded negoitations on an information security agreement enabling a new level of trust in exchanges between our two governments," Luxon said of the Japan deal.
"I hope to see strengthened security in defence cooperation," said Kishida.
The agreement has been at least two years in the making. It was first announced by then-Prime Minister Dame Jacinda Ardern during her trip to Tokyo in 2022.
Japan has - or is getting - similar deals with all the Five Eyes partners to bolster its intel on its neighbours like North Korea and China.
"There is no more important time than right now for our two countries to be engaging together to understand and respond to the serious regional issues in Japan's neighbourhood," said Luxon.
"Our two countries sharing fundamental values to strengthen strategic cooperate partnership is becoming important as never before," Kishida said.
After the meeting, Luxon had dinner with Kishida then hustled to the airport to start the long trip home on the NZDF 757.
That included a stopover in Cairns but the Prime Minister's office refused to let the media ask Luxon about the information deal, so Newshub had to ask his Foreign Affairs Minister about it in Wellington.
However, Winston Peters also wasn't so forthcoming.
So, Newshub went to the GCSB Minister instead.
"Well, the information will be quite secure information," Judith Collins said.