A minke whale is unloaded at a port on the island of Hokkaido.

A minke whale is unloaded at a port on the island of Hokkaido.

Japan has laid out a roadmap back to commercial whaling in its first comprehensive response to the International Court of Justice ban on its Antarctic "scientific" hunt.

The Japanese government announced plans to continue its North Pacific "research" whaling, though in reduced numbers, and set a path to a lethal Antarctic catch in late 2015.

The Fisheries Minister, Yoshimasa Hayashi, said the government's plans had given maximum consideration to the ICJ ruling.

"We will continue our research hunts aimed at collecting scientific data and seek to resume commercial whaling," Mr Hayashi told reporters in Tokyo.

Japan was forced to reconsider its hunts after Australia won a case against it at the ICJ, which ruled that the Antarctic program, known as JARPA II, breached International Whaling Commission rules for scientific research.

Japanese Fisheries Agency officials previously said the whalers would not go south in 2014-15, but Mr Hayashi indicated there would be a voyage next summer, limited to whale observation.

He confirmed a move back to the Antarctic with "hunting plans" in 2015-16, after Japan prepared a new program.

"We will carry out extensive studies in co-operation with ministries concerned to submit a new research program by this (northern) autumn to the International Whaling Commission, reflecting the criteria laid out in the verdict."

Environment Minister Greg Hunt cast doubt on Japan's' ability to persuade the IWC, which meets in Slovenia in September.

"Given the strength of the ICJ court order, it would seem the prospect of the IWC approving any further whaling is quite low," Mr Hunt said.

In its judgement the ICJ called on Japan to take account of the court's findings in any further scientific permits it issued to its whalers.

But ANU Professor of International Law Don Rothwell said the actual orders of the court covered the Antarctic hunt, and did not extend to the North Pacific.

"As such Japan is under no legal obligation to suspend that program for the time being," Prof. Rothwell said.

In the North Pacific hunt, to commence on 26 April, the quotas have been halved to a total 210, but still include 90 endangered sei whales.

Mr Hayashi said the scale of the hunt was being reduced in view of the ICJ verdict, but Greenpeace said it still flew in the face of the ICJ ruling.

Such a defiant stance would damage Japan's international standing at a time when whale meat stockpiles showed no sign of reducing, Greenpeace Japan executive director Junichi Sato said.

"The continued commercial hunting of whales supposedly for research purposes will surely be challenged legally, especially when endangered species are being targeted," Mr Sato said.

- with agencies