New Zealand led an international protest on Monday against Japan's plans to resume killing whales in the Southern Ocean, while Australia said it was considering further legal action.
A Japanese whaling fleet left port Saturday under tight security, marking the first hunt since the UN's top court last month ordered Tokyo to stop killing whales in the Antarctic.
Japanese whaling vessels left port Friday bound for the Southern Ocean on their annual hunt for the huge marine mammals, a media report and Greenpeace said.
Norwegian whale hunters have harpooned the first three whales of the year, nearly a month after the controversial hunting season began, the country's Fishermen's Sales Organisation said Wednesday.
A Japanese whaling fleet set sail for the Antarctic on Tuesday, on a mission to resume the slaughter after a one-year pause, with environmentalists slamming the move as a "crime against nature".
Japan announced Tuesday that it had wrapped up a whale hunt in the Pacific, the second campaign since the UN's top court ordered Tokyo to halt a separate slaughter in the Antarctic.
A whaling fleet anchored at a Japanese port Saturday after Tokyo said it would cancel its annual hunt for the first time in more than 25 years to abide by a UN court ruling.
Militant anti-whaling campaigners Sea Shepherd said Monday they were ambushed under the cover of darkness by a Japanese whaling fleet in a "ruthless assault" to disable their ship in the Southern Ocean.
Militant anti-whaling group Sea Shepherd on Monday dismissed as a "sham" Australian government plans to track Japan's annual whale hunt by air instead of by sea, saying it was a toothless and "cowardly" response.
Japan's annual whale hunt is a commercial slaughter of marine mammals dressed up as science, Australian lawyers argued Wednesday as they urged the United Nations' highest court to ban the hunt in the waters around Antarctica.