The thorny issue of rivalry in the South China Sea - one of Asia biggest security risks - was raised in formal talks between Prime Minister John Key and Chinese Premier Wen Jiabao.
The pair met in Phnom Penh last night ahead of the East Asia Summit - and the simmering territorial dispute was on the table, alongside trade and the slowing world economy.
China is embroiled in a number of spats with its neighbours over the mineral-rich waters and tensions flared at the 10-member Association of Southeast Asian Nations (ASEAN) conference also taking place in the capital yesterday.
US President Barack Obama flew into Cambodia last night for the EAS and is expected to urge China to resolve the dispute.
The last Asean meeting, earlier this year, was reportedly stymied by division and ended without a joint communique being signed.
Host Hun Sen is under pressure to keep the focus of the twin international pow-wow on regional growth. But Japanese Prime Minister Yoshihiko Noda yesterday raised the dispute - and was swiftly followed by Philippine President Benigno Aquino.
Beijing is thought to want to keep the dispute off the agenda at today's EAS leaders' meeting. But Key said the Chinese premier raised the matter during the talks at the city's Intercontinental Hotel.
"We did reiterate New Zealand's position - which is we don't take sides but we do want to see a peaceful resolution. That's in the interests of the region, and the world, for peace and stability in the South China Sea."
Key said Wen appreciated this stance - and hoped New Zealand would maintain it during today's EAS meeting.
"That we don't try and pick sides, we leave it to the parties to try and resolve those issues and to negotiate a way through it."
Overlapping tensions in the region are threatening to become a flashpoint. China, Vietnam, the Philippines, Brunei, Taiwan and Malaysia all lay claim to parts of the stretch of water - through which vital shipping lanes also run.
Japan and China are also in dispute over the Senkaku islands.
Key said the pair also compared notes on economic growth - and said Wen wants New Zealand to export more goods to China.
Today Key heads into a meeting of Trans Pacific Partnership leaders - where he will talk with Obama for the first time since his re-election.
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