Greens demand action against Japan whaling

The Greens are demanding the government turn up the heat on Japan as it prepares to send whaling ships to the Southern Ocean.

The Greens demand action against Japan as it prepares to send whaling ships to the Southern Ocean. (AAP)

The Greens are demanding the federal government use submarine contracts to pressure Japan out of sending whaling ships to the Southern Ocean.

The Japanese government says it will dispatch a "research" whaling mission to the Southern Ocean on Tuesday.

The announcement came as Attorney-General George Brandis told parliament Australia was making diplomatic representations at "the highest levels" in a bid to get Japan to change its mind.

He told the Senate on Monday the government would consider sending a Customs patrol vessel to the Southern Ocean if talks weren't successful.

Greens senator Peter Whish-Wilson says Japan are "thumbing their nose" at the Australian people.

He said Senator Brandis' reassurance that the issue of whaling wouldn't impact on bilateral relations between the nations meant it was "not being prioritised enough" by the Turnbull government.

Japan is currently in the running to build submarines for Australia and Senator Whish-Wilson wants the government to give them an ultimatum - either stop the harpoon boats going to the Southern Ocean or no submarine contract.

Japan's announcement is in defiance of international criticism and despite a UN legal decision that such activity disguises commercial hunts.

"The research ships will depart for new whale research in the Antarctic on December 1, 2015," the Fisheries Agency said in a statement on its website.

Tokyo has for years come under intense global pressure to stop hunts that opponents decry as inhumane but that Japan says are an inherent part of its traditional culture.

The United Nations' top legal body judged last year that Japan's so-called scientific whaling activity in the Southern Ocean was a front for commercial hunts.

The agency's statement said the "research period" for the mission would be from late December to early March.

It will include a "mother ship" as well as three other vessels with a total of 160 crew members.

Shadow attorney-general Mark Dreyfus said Japan's actions were an outrage and should be condemned.

It was an affront to the international rule of law and to Australia, which for 20 years sought to end Japanese whaling through diplomacy.

"Labor calls on the Turnbull government to bring all pressure to bear on Japan to renounce this irresponsible and illegal course of action," Mr Dreyfus told parliament.