Opposition parties are calling on the government to send navy ships to the Southern Ocean where another bitter battle between Japanese whalers and protesters looks set to break out.
Japan has announced it will toughen security around its whaling fleet in response to the promise of dramatic attacks by anti-whaling group Sea Shepherd.
Foreign Affairs Minister Murray McCully is urging Japan not to send its whaling fleet this summer, saying the decision to do so is "entirely disrespectful" of strong concerns held by Australians and New Zealanders.
Labour and the Greens don't think that's enough, and both parties said on Wednesday that navy ships should be sent to monitor the situation.
"New Zealanders don't like sitting on the sidelines when bad things are happening," Labour's foreign affairs spokeswoman Maryan Street said.
"Labour believes there is a case for New Zealand naval vessels to be sent to monitor activities."
The Greens said offshore patrol ships should be sent.
"The government says it is committed to saving the whales but doesn't have the courage to commit any resources to do so," Greens oceans spokesman Gareth Hughes said.
In Japan, Fisheries Minister Michihiko Kano said on Tuesday that measures would be taken to ensure the whalers' safety, and that this year's hunt would go ahead.
"We intend to carry out the research after enhancing measures to assure that it is not obstructed," he said.
The hunt is expected to begin in December.
Sea Shepherd successfully disrupted last season's efforts and says the Japanese whalers obtained only 17 per cent of their quota due to direct action by the group.
Earlier this week, it announced plans to send 100 volunteers to the Southern Ocean and warned they were prepared to lose lives if necessary.
"They will have to kill us to prevent us from intervening once again," Sea Shepherd leader Captain Paul Watson said.
Mr McCully said he was alarmed by Mr Watson's statements and urged both parties not to put lives or the Antarctic environment at risk.
In Australia, the federal government condemned Japan's whaling program in a statement released on Tuesday.
"Australia remains resolute in its opposition to all commercial whaling, including Japan's so-called 'scientific whaling'," the join statement issued by Foreign Minister Kevin Rudd, Attorney General Robert McClelland and Environment Minister Tony Burke said.
But Capt Watson dismissed the comments.
"It is all just talk," he told AAP from the United States.
"Unless they send a boat down there and escort the Japanese fleet out of there they are not doing anything," he said.
Australian Greens leader Bob Brown said the Australian navy and federal police should be involved in pursuing and investigating Japanese whalers.
NZN