The New Zealand Defence Force says a military plane accused by China of “harassment” has spotted possible illicit activity while monitoring shipping near North Korea.

A series of maritime patrols over the Yellow and East China Seas conducted by a Royal New Zealand Air Force P-8A Poseidon aircraft observed a possible ship-to-ship transfer of illicit goods, reported 35 vessels of interest and broadcast eight deterrence messages, the New Zealand Defence Force (NZDF) said.

The patrols, which have now concluded, were part of an operation to monitor North Korean evasion of United Nations (UN) Security Council sanctions, which the NZDF says it has been contributing to since 2018.

It comes after China accused the NZ P-8A Poseidon aircraft of “harassment” earlier this month, with Ministry of National Defence spokesman Zhang Xiaogang urging New Zealand to “exercise strict restraint” and “immediately stop irresponsible and disruptive acts”.

The aircraft was singled out by Zhang at a press conference in Beijing on April 17, according to local media.

“A P-8A anti-submarine patrol aircraft of the New Zealand Air Force has conducted frequent close-in reconnaissance and harassment in the airspace and waters of the Yellow Sea and East China Sea,” Zhang said, according to Global Times, the Chinese Communist Party newspaper.

A Royal New Zealand Air Force P-8A Poseidon aircraft has carried out maritime patrols over international waters, monitoring North Korean evasion of United Nations Security Council sanctions. Photo / NZDF

The Chinese military gave warnings to the plane and lodged “stern representations with the New Zealand side”, he said.

Following the conclusion of the patrols, NZDF said: “New Zealand is a member of the Pacific Security Maritime Exchange, a partnership of nations working together to detect evasions of UN sanctions which are aimed at curbing North Korea’s nuclear and ballistic missile programmes.

“Maritime patrols report vessels suspected of trafficking refined petroleum to North Korea and exporting commodities such as coal, iron ore and sand used to fund North Korea’s nuclear and ballistic missile production.

“Suspected sanctions evasions are reported to the UN, and diplomatic channels are also used to raise concerns with the flag states of vessels.

“The completed patrols by the P-8A were conducted in the Yellow Sea and East China Sea, where evasions of UN sanctions by North Korea occur.”

Air Component Commander Air Commodore Andy Scott added that the NZDF provided an important contribution to efforts to monitor the UN resolutions against illicit ship-to-ship transfers.

“The evidence captured of activities that were occurring in the East China and Yellow Seas allows authorities to take action against ships that may still be operating in contravention of this resolution,” he said.

“The upholding of international law is critically important for regional security and we are proud of our ability to contribute to this important work.”