The International Court of Justice has ordered Japan to cease its whaling programme immediately.
The move comes after Australia won an international lawsuit against Tokyo's Southern Ocean whaling programme.
According to news.com.au, presiding Judge Peter Tomka of Slovakia said Japan had not justified the large number of minke whales it takes under its programme.
Japan has said it will abide by the decision, but it does not necessarily mean a permanent end to whaling.
The United Nation's court ordered Japan to halt whaling until the programme has been revamped, the report said.
The ICJ, by 12 votes to four, said Japan had not acted in compliance with its obligations under the international whaling convention, the report added.
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