Japanese whalers reported to be in New Zealand waters should be forced to leave, the Green Party says.
The call follows a report that anti-whaling activists Sea Shepherd are seeking refuge from Japanese whaling ships in the Auckland Islands while refuelling.
The activists are trying to close in on whaling ship Nisshin Maru, but are being tailed by other whaling ships, the Yushin Maru No. 3 and Shonan Maru No. 2, to prevent it from doing so.
Green party oceans spokesperson Gareth Hughes said the Government should do everything in its power to make the whalers leave.
"It is offensive that Japanese whalers are in New Zealand waters," Hughes said in a statement.
"The Government should seek urgent legal advice to determine if the Marine Mammal Act gives the Government grounds to expel Japanese whalers."
Hughes said if New Zealand cannot act legally, the laws should be changed.
"Chile has passed legislation that bans the transport of whale meat through their waters, and we can do the same."
The Nisshin Maru is currently whaling in the Antarctic and is likely to have taken hundreds of whales already.
Tensions between Sea Shepherd and the whalers flared in recent months after the activists reported flammable grenades and high-powered hoses were aimed at their ships.