China will not be singled out for criticism on issues such as human rights and regional security, Prime Minister Jacinda Ardern told a New Zealand Institute of International Affairs seminar in her first major foreign policy speech since taking office in October.

Speaking to a venue packed with foreign ambassadors, New Zealand diplomats and defence chiefs, and foreign policy experts, Ardern made no mention of this week's move to change China's constitution to allow its President Xi Jinping to rule for more than the current 10-year maximum, acknowledging that "China's global influence has grown along with its economic weight".

"Its leadership on issues like climate change and trade liberalisation could add momentum to our collective efforts in those areas," she said in a section of her speech advocating the importance of globally accepted rules for trade and security. "Naturally, there are areas where we do not see eye to eye with China. My government will speak honestly and openly with our friends in Beijing. Whether it is about human rights, pursuing our trade interests, or the security and stability of our region.

"Taking that approach isn't about singling countries out, but about taking a consistent approach on the issues and principles that matter to us."


Ardern said differences of opinion with other major partners, Australia and the United States, were inevitable but the relationships were robust enough to withstand such strains.

"Australia is our only ally and closest friend. As in any relationship, we will have our differences. But unquestionably Australia constitutes a vital source of resilience for our economy and is our key partner for New Zealand in the wider world," said Ardern, who will meet with Australian Prime Minister Malcolm Turnbull in Sydney on Friday.

"New Zealand's relationship with the United States is also fundamental," she said. "For over 70 years, the values and interests of New Zealand and the United States have intersected more often than not. The sheer size and dynamism of the world's biggest economy, America's capacity for ideas and the energy of its people give it enormous scope to help shape a better world.

"But the real strength of any important relationship lies in its breadth and ability to encompass difference. For example, we were disappointed at the United States' withdrawal from the Paris agreement and some of its positioning on trade. But our relationship with the US is certainly robust enough to withstand those differences."

Answering questions, Ardern said "the biggest threat" for New Zealand was the erosion of global rules-based institutions.

Rules were important but "if they are flouted, what's the point?"

However, governments had to build "social licence" among its own people to maintain support for those global structures.

On trade, Ardern repeated the government's intention to take a more inclusive and transparent approach to free-trade agreements, defending the decision to go ahead with the upgraded Comprehensive and Progressive Trans-Pacific Partnership.


"We ignore the interaction of global developments on our domestic population at our peril. Overseas experience, and our own, tells us that if we want to retain the values of being outward looking, engaged in global institutions, welcoming of trade and direct investment, we must build the social licence for that.

"The last APEC meeting in Vietnam, for instance, had a strong focus on creating greater inclusiveness around the trade agenda. We want to take that a step further.

"The experience of watching the early interactions of TPP, and being part of the final negotiations taught me a lot. It reaffirmed my belief that trade has the ability to support sustainable, productive and inclusive growth if that is the agenda you enter negotiations with," she said. "That is why you will see us establish a different framework for trade negotiations, one where we more openly pursue the interests of our regions, SMEs, Maori and women."

On wider international issues, Ardern announced the government's intention to ratify the Treaty of the Prohibition of Nuclear Weapons, signed last year, and the reinstatement of the Cabinet portfolio of Minister of Disarmament and Arms Control, which would be held by Foreign Minister Winston Peters.