Japan is defending its controversial whaling practices at the UN's highest court as Australia charges that Tokyo's scientific whale research program is really commercial whaling in disguise.

Public hearings are underway at the International Court of Justice (ICJ) in The Hague as the first round of oral arguments began Wednesday with Australia contending that Japan's position that its whaling activities are rooted in scientific purpose "is not only untenable, it is dangerous" for whale populations, the BBC reported.

As the hearings began, Bill Campbell, one of Australia's lawyers in the case, told the court that "Japan seeks to cloak its commercial whaling under the labcoat of science," the APF reported.

Campbell said that Japan's JARPA and JARPA II research programs, which have killed more than 10,000 whales since 1988, are not science and that whaling operations in the Southern Ocean are stressing Australia's otherwise "excellent" relationship with Japan.

Australia contends that Japan is in breach of international conventions and the obligation to preserve marine mammals and their environment by exploiting a loophole in the international moratorium of commercial that allows for lethal scientific research, according to the AFP. Norway and Iceland openly defy the 1986 commercial whaling moratorium set forth by the International Whaling Commission.

Japan's whaling fleet leaves for the Southern Ocean each November or December and catches fin whales and minke whales for what it says are scientific purposes. Meat from the whales is sold commercially, the BBC reports.

"Australia's views on whaling are well established. We strongly oppose all commercial whaling, including so-called 'scientific' whale hunting by Japan," said Attorney-General Mark Dreyfus, who is also representing Australia at the ICJ.

Japan asserts that its whaling program is scientific and that it operates within the existing framework of laws and treaty obligations.

Japan's Deputy Foreign Minister Koji Tsuruoka told the court that "Australia's claim is invalid. Japan's research whaling has been conducted for scientific research in accordance with international law," the AFP reported.

Tsuruoka said Japan is "proud of its tradition of living in harmony with nature, and utilizing living resources while respecting their sustainability."

Japanese delegation spokesman Noriyuki Shikata told the AFP that Japan is "very much paying attention to the conservation of whales," and that Japanese whaling programs act as important research in understanding whale stocks in the Antarctic.

Australia will use the rest of this week to make its case against Japan. Next Tuesday Japan will have three days of its own for counter arguments. A further round of arguments, including an intervention by New Zealand, will take place before the trail is expected to finish July 16. However, a ruling is not expected until several months later. The IJC's decision is considered legally binding.