Winston Peters is in Japan for the Foreign Ministers' meeting of the G20 grouping of countries.
Foreign Minister Winston Peters has used a rare opportunity at the table of the world's largest economies to call some out for unfair trade practices and on climate change.
Peters was in Japan for the Foreign Ministers' meeting of the G20 grouping of countries as one of nine "invited" countries.
Peters used it as a chance to put in a plea for the large countries not to forget the small countries, such as the Pacific Islands.
In the process, he took a tacit dig at countries which still offered subsidies or Government assistance to fossil fuel industries.
The G20 has resolved to phase out subsidises for fossil fuels, but many countries in it continue to support the sectors - including Australia with coal mining.
Peters said Pacific countries had called for urgent action on this and New Zealand was part of the effort to make it happen.
"This must be a global priority. We cannot continue to subsidise the climate change we seek to avert."
Peters said the large countries should not forget the impact on the small.
"Pacific Islands countries manage the world's largest oceans, and they are on the front lines of the impacts of global climate change.
For some it is an existential threat to their very survival. Yet because Pacific Island countries have small populations and are geographically remote, their perspective is rarely heard at the G20."
He said while there was work being led by the G20 on cleaning up oceans and plastic waste "much more must be done".
Peters also raised the Christchurch Call with his fellow ministers, New Zealand's response to the spread of violent extremism on social media after the Christchurch terror attacks.
Peters also spoke during a session on trade, including reform of the World Trade Organisation, at a time of rising protectionism predominantly driven by the United States.
Peters said the scale of restrictive practices was "unprecedented" through both tariff and subsidies for domestic industries, including agriculture, making it hard for exporters.
Many of those New Zealand is trying to get a free trade deal were in the room - including the US Deputy Secretary of State John Sullivan, the EU's Foreign representative Federica Mogherini.
Some of the G20 members were also concerned about rising protectionism and the increasing powerlessness of the World Trade Organisation to resolve complaints.
They included Japan, whose Foreign Minister Toshimitsu Motegi said ensuring the WTO operated effectively was a priority as trust in the multilateral trade system wavered.
There was also some fear that India will drop out of the newest multilateral trade agreement New Zealand is involved in - the RCEP [Regional Comprehensive Economic Partnership].
Most countries involved have largely agreed on the deal, but India is still uncertain.
Mortegi said Japan was something of "standard bearer" in free trade having signed the TPP, a bilateral deal with the US, and the EU deal. He had told G20 members that the RCEP agreement was now at "a critical juncture."
"I explained the significance of concluding the RCEP with all 16 countries on board."
Peters had said in advance of the meeting that he hoped to push home New Zealand's desire for a swift conclusion to trade negotiations with the EU. While in Japan, he sat next to Mogherini for dinner, and had one-on-one meetings with some EU countries, including Germany and Spain.
He also met with the Foreign Ministers of Indonesia, Saudi Arabia, and Singapore, and caught up briefly with Russia's Sergey Lavrov and Australia's Marise Payne.