The UN's top court on Monday ordered Japan to end its annual Antarctic whale hunt, saying in a landmark ruling that the programme was a commercial activity disguised as science.
"Japan shall revoke any existant authorisation, permit or licence granted in relation to JARPA II (research programme) and refrain from granting any further permits in pursuance to the programme," the International Court of Justice's Judge Peter Tomka said.
Agreeing with Australia, which in 2010 hauled Japan before the Hague-based ICJ in a bid to end whale hunting in the Southern Ocean, Tomka said that "special permissions granted by Japan are not for purposes of scientific research."
"The evidence does not establish that the programme's design and implementation are reasonable in relation to its stated (scientific) objectives," Tomka said.
While Norway and Iceland have commercial whaling programmes in spite of a 1986 International Whaling Commission (IWC) moratorium, Japan insisted its programme is scientific, while admitting that the resulting meat ends up on plates back home.
Tokyo was accused of exploiting a legal loophole in the 1986 ban on commercial whaling that allowed the practice to collect scientific data.
But Tomka said that "funding considerations, rather than strictly scientific criteria, played a role in the programme's design."
Canberra said since 1988 Japan has slaughtered more than 10,000 whales under the programme, putting the Asian nation in breach of international conventions and its obligation to preserve marine mammals and their environment.
- 'All eyes are now on Japan' -
"Neither commercial nor scientific whaling have any place in the 21st century," said Claire Bass, Head of Wildlife Campaigns at World Society for the Protection of Animals (WSPA), after the ruling.
"This decision sends a clear message to governments around the world that the exploitation of animals will no longer be tolerated and animals must be protected at the highest level," Bass said in an email to AFP.
"All eyes are now on Japan to respect this decision," she said.
In its application before the world court, Australia accused Japan of failing to "observe in good faith the zero catch limit in relation to the killing of whales".
A Japanese Fisheries Agency official told AFP ahead of the ruling that it maintained the view that "Japan's whaling is purely for the purposes of obtaining scientific data, so that whale resources can be sustainably maintained".
Tokyo has consistently defended the practice of eating whale meat as a culinary tradition and vowed it would "never stop whaling".
But Japanese officials told AFP ahead of the ruling that Tokyo would accept the verdict of the ICJ, set up after World War II to rule in disputes between countries.
Japan in April last year announced its whaling haul from the Southern Ocean was at a record low because of "unforgivable sabotage" by activists from the militant environmental group Sea Shepherd.
Sea Shepherd had called the ICJ case make-or-break for whales in the Southern Ocean.
Defiant Japanese Fisheries Minister Yoshimasa Hayashi last year vowed Japan would never stop whaling, a "long tradition and culture" in his country, although officials told AFP ahead of the ruling that Tokyo would accept the verdict.
Established in 1945, the ICJ is the UN's highest judicial body and the only one of five principal UN bodies not located in New York.
The ICJ's judgements are binding and cannot be appealed.