NZ's support of ruling rejecting maritime claim 'seriously undermines' relationship, says China

China has rebuked New Zealand for its continued support of an arbitration ruling that rejects China's maritime claims over the South China Sea.

New Zealand has signed up to a statement on the 10th anniversary of the landmark ruling, saying it is legally binding and definitive.

But China's ambassador to New Zealand says the arbitration award is illegal, and New Zealand's continued support undermines the relationship.

In July 2016, a tribunal at the Hague ruled that China had no historical exclusive control over the South China Sea, backing a case brought by the Philippines, and that the 'nine-dash line' had no legal basis under the United Nations Convention on the Law of the Sea (UNCLOS).

China has never recognised the decision.

On the 10th anniversary of the Philippines-China South China Sea Arbitral Tribunal Award, the governments of 14 nations issued a joint statement to commemorate it, and set out their "unwavering commitment to maintaining a free and open Indo-Pacific that is peaceful, stable, and rules-based, anchored in international law".

Along with New Zealand, the governments of Australia, Canada, Estonia, Germany, Italy, Japan, Latvia, Lithuania, the Philippines, Romania, Slovenia, the United Kingdom and the United States of America issued the statement.

"We reaffirm that maritime disputes must be resolved peacefully and in accordance with UNCLOS. We reaffirm that the award rendered 10 years ago by the Arbitral Tribunal is a significant milestone and is final, legally binding, and definitive between China and the Philippines with respect to the maritime entitlements and claims addressed by the Arbitral Tribunal."

The governments said there was no legal basis for China's "expansive maritime claims" in the South China Sea, including those based on "historic rights," and reiterated their "strong opposition" to any destabilising or unilateral actions "including by force or coercion that threaten peace and stability in the region".

Responding to the statement, China's ambassador to New Zealand Wang Xiaolong said the "continued playing up" of the award by "certain countries" was inconsistent with the trend of peace and stability in the region, and urged them to "earnestly respect China's territorial sovereignty and maritime rights and interests in the South China Sea, stop stirring up trouble over the South China Sea issue, and cease undermining peace and stability in the South China Sea".

Singling out New Zealand in particular, Wang said New Zealand's involvement in the statement "clearly deviates from the understanding reached by our leaders and seriously undermines the foundation of healthy and stable relationship".

Wang said China had no intention to hurt the interests of New Zealand, and remained committed to a mutually respectful and beneficial relationship.

"However, it takes two to tango," he said.

"And no one should underestimate our resolve and capability to defend our legitimate rights and interests. We urge the New Zealand side to cease immediately violating China's interests and return to the path of promoting the development of the bilateral relationship on the basis of mutual respect and mutual benefit, and resolving disputes through constructive dialogues, with a view to avoiding further damage to the relationship."

A spokesperson for foreign affairs minister Winston Peters said New Zealand stood by the joint statement, and had no further comment to make.

The European Union issued its own statement, saying the ruling was "final and legally binding," and it must be respected and fully implemented.

"The EU underlines the critical importance of upholding the freedoms, rights and duties set out in UNCLOS, in particular the freedom of navigation and overflight, including the right of transit passage, as essential to regional stability, global security, and the maintenance of safe, free and open sea routes," the statement said.

It is not the first time China has clashed with New Zealand over the dispute.

In 2016, then-defence minister Gerry Brownlee was rebuked at a security forum in Beijing over New Zealand's support for the arbitral process.