The UN's top court has ordered Japan to stop its annual whale hunt in the Antarctic, rejecting Tokyo's argument that it is for scientific purposes, in an emotive case activists said was make-or-break for the giant mammal's future.

"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 on Monday.

Australia hauled Japan to the ICJ in an attempt to torpedo whale hunting in the Southern Ocean, a practice Canberra says is a thinly-disguised commercial exploit under a cover of scientific research.

While Norway and Iceland have commercial whaling programmes in spite of a 1986 International Whaling Commission (IWC) moratorium, Japan insists its programme is scientific, while admitting that the resulting meat ends up on plates back home.

Tokyo is accused of exploiting a legal loophole in the 1986 ban on commercial whaling that allows the practice to collect scientific data.

10,000 'slaughtered'

Australia asked the world court to order Japan to stop its JARPA II research programme and revoke "any authorisations, permits or licences" to hunt whales in the region.

Tokyo vowed to vigorously defend the practice which it maintained was for scientific purposes only.

But Canberra said since 1988 Japan has slaughtered more than 10,000 whales under the programme, allegedly putting the Asian nation in breach of international conventions and its obligation to preserve marine mammals and their environment.

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".

Japan in April 2013, announced its whaling haul from the Southern Ocean was at a record low because of "unforgivable sabotage" by activists from the environmental group Sea Shepherd.