The world's maritime watchdog has agreed to a landmark deal for shipping companies to pay for their carbon dioxide emissions - but New Zealand abstained from the vote.
The Ministry of Transport said New Zealand was preserving its position "while officials undertake further work to analyse the draft resolution".
The ministry said officials would give further advice to ministers before any formal adoption at the next meeting of the International Maritime Organisation (IMO) in October.
The deal was 10 years in the making and covers the vast majority of the world's commercial shipping.
Although shipping makes about 3% of global emissions, international shipping, like aviation, isn't covered by countries' climate pledges under the Paris Agreement, leaving it outside the main deal for tackling climate change globally.
In 2023, countries in the IMO unanimously agreed that the international shipping sector would cut its planet-heating emissions to net zero by or about 2050.
Under the deal agreed last week, starting in 2028, ships must lower emissions over time by becoming more efficient or switching to cleaner fuels, and would pay penalties for emissions over a certain threshold.
The Guardian reported that the $US10 billion ($NZ16.8 billion) a year expected to be raised by the levies would likely be used by the shipping industry to introduce clean technologies.
Many small Pacific nations abstained from the vote, with local media reporting that many Pacific leaders expressed the view that the deal was too little too late and wouldn't deliver them the payments they needed to adapt to climate change.
Fiji, Kiribati, Vanuatu, Marshall Islands and Tuvalu were among those who chose to abstain, while Cook Islands, Tokelau and Samoa voted for the agreement.
Saudi Arabia, Russia, the United Arab Emirates and other fossil-fuel states opposed the rules and forced the agreement to a vote. They then voted against the deal.
However, a comfortable majority of countries voted in favour, including China, France, Singapore, Brazil, UK, Germany, Canada, Denmark, Chile, Greece and Indonesia.
The US pulled out of negotiations, but the deal went ahead anyway.
The deal was seen as a compromise to get some form of carbon pricing over the line.
Shipping emissions are particularly relevant to New Zealand, because the vast majority of exports travel by ship to distant markets, and exporters such as Fonterra and Zespri are under pressure from their customers to show they have workable plans to cut their emissions.
According to Zespri, shipping carries 99% of New Zealand's trade by volume and about 80% by value.
The kiwifruit exporter has previously said its customers were already demanding plans to lower the company's emissions and its goal of growing its exports would require tackling carbon emissions.
Because kiwifruit itself is a low-carbon product, between a third and a half of the company's climate impact comes from transporting the fruit.
Zespri and a shipping partner have trialled burning biofuel made from blended cooking oil between Hong Kong and Tauranga, and the company is studying a possible low-emissions shipping corridor between Tauranga and Belgium via the Panama Canal.
