Former attorney-general Mark Dreyfus has called on the federal government to work with Japan on non-lethal whaling research after the UN's top court ruled the nation's annual Southern Ocean hunt is not a scientific program.

In a surprise judgment, the International Court of Justice on Monday backed a landmark case put by Australia and demanded Japan cease its whaling program "with immediate effect".

Mr Dreyfus, who was involved in bringing the case to court, said "on paper" the judgment could leave the door open for the slaughter of some whales.

"I'm calling on the government to work with Japan on non-lethal research, so that there won't be killings of whales in the Southern Ocean ever again," he told ABC radio on Tuesday.

Australian scientists already pursue non-lethal scientific whale research using satellite trackers to monitor movements and diet.

Mr Dreyfus also said he expected to see more countries being held to account on their environmental obligations under signed treaties.

Source: aap