Climate Change Minister James Shaw has evoked the nuclear-free and women's suffrage movements in telling to a UN conference that New Zealand has turned a corner and will now be a world leader on climate change.

"A little over 30 years ago a New Zealand Prime Minister, David Lange, declared that nuclear weapons were morally indefensible and that we would no longer play any part in the arms race that threatened to extinguish all life on earth," Shaw told the COP23 conference in Bonn, Germany, in delivering New Zealand's national statement overnight.

"We were the first country where women won the right to vote. We were around the table at the formation of the United Nations. And we became a nuclear-free nation in the face of the Cold War's deadly logic.

"Our new Government has committed to the goal of becoming a net zero emission economy by the year 2050, and to join with the high ambition countries leading the worldwide fight against climate change."


Shaw said there was no room for half-commitments.

"Ask the citizens of Houston if Hurricane Harvey would meet them half-way. Ask the people of Tuvalu, the Marshall Islands, or Kiribati, or Tokelau - how compromising is the rising sea?"

The conference is discussing how to implement the Paris Agreement, which aims to keep global warming to 1.5C.

Shaw told the conference that New Zealand would do its part through a range of policies, including planting 1 billion trees, turning the Government's fleet electric, and building sustainable industries.

At COP23, New Zealand has also signed up to the Powering Past Coal alliance, which is committed to phasing out the use of coal for electricity generation by 2030.

Shaw told the Herald New Zealand's only coal-burning generators at Huntly are to be decommissioned by 2025.

"But symbolically it is really important, and the more countries that get in on it, the better."

Shaw said the alliance was more popular than anticipated.


"As it was launching, security wasn't letting people through because there were so many people trying to get in, they were afraid the floor would collapse."

He said the reaction at COP23 to New Zealand's new direction had caused a stir.

"When I got here, everyone was talking about how Jacinda had said this was the nuclear-free moment of our generation. I wasn't really anticipating the level of reaction that we're getting from the international community about the shift. It's been quite extraordinary, really warmly received."

He said New Zealand's small size was no excuse for inaction.

"If you add up all the countries who contribute less than 1 per cent, we collectively contribute almost a quarter of global climate pollution.

"There are a number of countries that have committed to net zero, and there are a number trying to squirrel out of the Paris Agreement in one way, shape or form, so it really helps that there are countries like New Zealand that are making that commitment."