Beijing said Friday that a New Zealand P-8A anti-submarine patrol aircraft had engaged in "close-in reconnaissance and harassment in the airspace" in the Yellow and East China seas.

A spokesman for China's foreign ministry told reporters at a press briefing that the moves "undermined China's security interests, increased risks of misunderstanding and miscalculation, and gravely disrupted the order of civil aviation in relevant airspace".

In response the New Zealand Defence Force (NZDF) said the aircraft had been carrying out UN-mandated monitoring of North Korean sanctions in the region.

"These activities are not directed at China but rather aim to monitor evasions of United Nations sanctions on North Korea, which do occur in the Yellow Sea and East China Sea," an NZDF spokesperson said.

"The New Zealand Defence Force crew operated professionally and in accordance with international law and civil aviation procedures for the region," they added.

"NZDF has reviewed the routes flown and all available information. We have no data which indicates they disrupted civil aviation."

The NZDF spokesperson said there had been "dialogue" between Wellington and Beijing over the issue.