The Ministry of Foreign Affairs has summoned a senior Japanese diplomat to express its anger over Japanese whalers entering New Zealand's marine waters after being asked not to.
Foreign Affairs Minister Murray McCully is promising further action to ensure the Japanese government understands the seriousness of what happened.
Last week, a ship involved in security for Japan's whaling fleet followed a vessel belonging to conservation group Sea Shepherd into New Zealand's exclusive economic zone in the Southern Ocean, though it stayed outside the country's territorial waters.
McCully says while the Japanese decision to ignore New Zealand's wishes has no legal implications, it was unhelpful, disrespectful and short-sighted.