An international relations professor is warning China's activity in the Tasman Sea shows it wants to establish a permanent military presence in the Pacific, and New Zealand must prepare for that.

Australia's defense forces, joined by New Zealand, have been monitoring Chinese navy vessels since they were spotted last week.

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Prime Minister Christopher Luxon earlier said New Zealand "have been continuously monitoring, tracking and shadowing the movements of this fleet".

Australia warned airlines flying between Australian airports and New Zealand to beware of Chinese warships potentially conducting a live-fire exercise in the Tasman Sea

Crew members on board a New Zealand navy frigate shadowing Chinese military ships have reportedly seen behaviour “consistent with a live-fire activity”. It comes as airlines – including Air New Zealand – have been forced to modify their flight paths after warnings by the Chinese military to avoid airspace between Australia and New Zealand before live-fire military drills in the Tasman Sea.

MELBOURNE, Australia (AP) — Australia warned international airlines flying between Australian airports and New Zealand to beware of Chinese warships conducting a live-fire exercise in the Tasman Sea, Foreign Minister Penny Wong said Friday.

Military exercises by the Chinese navy in international waters southeast of Australia on Friday forced commercial flights transiting the Tasman Sea between Australia and New Zealand to divert.

China's naval exercise in the Tasman Sea has put Australia and New Zealand on alert, with Canberra calling it "unusual".