New Zealand announced Friday it would join Australia’s bid to take Japan to court over its whaling, which Tokyo insists is for ‘scientific purposes’.

New Zealand formally joined Australia in challenging Japan’s claim that its whaling was ‘scientific’ at the International Court of Justice, AFP reports.

Foreign Minister Murray McCully said he was disappointed diplomatic initiatives failed to persuade Japan to halt whaling operations in the Southern Ocean.

“New Zealand has worked hard with Japan for over three years to try and find a permanent solution to whaling in the Southern Ocean,” Mr. McCully said in a statement.

“The government will continue to use all avenues possible to try to bring a halt to Japanese whaling”.

Under an international treaty, commercial whaling was banned but Japan continues to step around that due to a loophole.

Australia launched a legal action in December 2010 while New Zealand resorted to diplomatic channels to persuade Japan to drop whaling which is considered a tradition.