The Ministry of Foreign Affairs and Trade earlier confirmed Christopher Luxon was scheduled to be on the group call of up to 40 leaders overnight (NZ time) focusing on unlocking the strait through diplomatic means.
The United States-Israeli war with Iran, which began on February 28 this year, has destabilised the Middle East and rocked global energy markets by effectively closing the strait, an important shipping channel.
In a statement posted to social media, Luxon said conflict in the Middle East had driven up the price of fuel and could impact other everyday goods.
"Freedom of navigation, international law, stable and predictable trade routes are essential to our economy. The same goes for our friends who are hurting across the Indo-Pacific and our Pacific Islands neighbours.
"While we were meeting, it was encouraging to see Iran announce it would re-open parts of the Strait. Of course, this still remains a very fragile situation and it is an important moment to work together with partners."
Some 50 countries from Europe, Asia and the Middle East joined the video conference chaired by France and Britain that followed on initial military planning and aimed to send a signal to Washington.
Iran, which said it was ready to open the strait, has largely closed it to ships other than its own since the start of US-Israeli airstrikes against in February. On Monday (local time), Washington imposed a blockade on ships entering or leaving Iranian ports.
Trump has called on other countries to help enforce the blockade and has criticised NATO allies for not doing so, but just as the Paris talks concluded, Trump said he had told NATO to stay away.
Britain, France and others say joining the blockade would amount to entering the war, but that they would be willing to help keep the strait open once there was a lasting ceasefire or the conflict ended.
French President Emmanuel Macron said the meeting had allowed them to send a united message to demand the immediate and unconditional reopening of the strait, through which around a fifth of the world's oil and liquefied natural gas usually passes, and restoration of free passage.
"We all oppose any restriction, anything that would amount, in effect, to an attempt to privatise the strait, and obviously any toll system," Macron told reporters.
He said part of French naval assets currently deployed in the eastern Mediterranean and Red Sea could be used for the mission.
"We will take this forward with a military plan conference in London next week where we will announce more detail on the composition of the mission, and over a dozen countries have already offered to contribute assets," British Prime Minister Sir Keir Starmer said.
The initiative being discussed did not, for now, include the US or Iran, though European diplomats said any realistic mission would ultimately need to be coordinated with both.
German Chancellor Friedrich Merz said his country was prepared to contribute to the mission, adding that input from the US would also be "desirable" and that he did not want the issue to become a "stress test" for transatlantic relations.
Several diplomats said the mission might never materialise if the situation in the Strait of Hormuz returned to normal.
Others said shipping companies and insurers could seek such a deployment during a transitional phase to provide reassurance.
"It can involve intelligence sharing, mine-clearance capabilities, military escorts, information procedures with neighbouring countries and more," a senior French official said.
"The objective is clear, and the resources deployed will naturally depend on the situation.
- RNZ and Reuters
