THE HAGUE, Netherlands » The future of whaling in Japan was thrown into doubt after the International Court of Justice ruled Monday that the nation’s annual hunt in the Antarctic was not really for scientific purposes — as Tokyo had claimed — and ordered it halted.

The ruling was a major victory for whaling opponents, as it ends for now one of the world’s biggest whale hunts, for minkes in the icy Southern Ocean. The judgment was praised by Australia, which brought the case against Japan in 2010, and by environmentalists, who have been seeking an end to whaling since the 1970s on ethical grounds.

The world court’s decision leaves Japan with a tough choice between ending whaling outright — despite past claims that it would never abandon such a deep-seated cultural practice — or redesigning its program to make it a scientific endeavor after all.

Japan has previously all but ruled out joining Norway and Iceland in openly flouting the international consensus against commercial whaling.

Former Australian environment minister Peter Garrett, who oversaw the suit’s launch, said he felt vindicated.

"I’m absolutely over the moon, for all those people who wanted to see the charade of scientific whaling cease once and for all," Garrett told Australian Broadcasting Corp. radio. "I think (this) means without any shadow of a doubt that we won’t see the taking of whales in the Southern Ocean in the name of science."

In a 12-4 majority judgment, the U.N. court sided with Australia, finding that Japan’s program fell short of following scientific methods. For instance, judges said Japan had given no reason for its target of 850 minke whales annually and often failed to meet the target. It gave no defense of why it needed to kill that many to study them. And the "research" program had produced just two peer-reviewed scientific papers since 2005.

"The court concludes that the special permits granted by Japan for the killing, taking, and treating of whales … are not ‘for purposes of scientific research’," presiding judge Peter Tomka said.

The court ordered Japan to grant no further permits for its current Antarctic program.

Japan had argued its study was aimed at determining whether commercial hunting could be conducted on a sustainable basis.

The International Court of Justice is the U.N.’s court for resolving disputes between nations and its ruling are binding and not subject to appeal. Although sovereign countries can and occasionally do ignore them at times, both Japan and Australia had pledged to abide by this decision.

Japan’s Chief Cabinet Secretary Yoshihide Suga said Monday the government will keep its word and obey the court "as a state that places a great importance on the international legal order."

However, he criticized the International Whaling Commission, the main international body that regulates whaling, which ordered a moratorium on all commercial whaling in 1986. That moratorium has remained in place despite recommendations from its own scientific committee that some whale species are robust enough to support a whaling industry.

Suga said Japan has cooperated with the IWC for decades "despite the deep divisions within the Commission, and its inability in recent years to function effectively."

He left the question of what Japan will do next unanswered.

Membership in the International Whaling Commission is voluntary and Norway and Iceland have simply decided to ignore its mandates while remaining members.

Under IWC rules, countries are allowed to issue themselves as many permits as they see fit to kill whales for scientific purposes. The permits are subject to a nonbinding review by a 200-member scientific committee that has been critical of Japan for many of the same reasons outlined by the world court in Monday’s ruling.

Norway hunts around 500 minke whales in the northeast Atlantic each year, while Iceland hunts roughly 50. Japan has a second scientific program in the north Pacific which culls around 100 minke whales annually. That program may now also be open to challenge because it was not covered in the Australian suit.

Activist Pete Bethune, a New Zealander who has clashed frequently with Japanese whalers in attempts to stop their hunt, said "justice was served" by Monday’s ruling.

"The court dissected their scientific program, pulled it to bits and it proved that the amount of science is tiny relative to the commercial aspects," he said outside the courtroom.

The ruling left the door open for Japan to launch a new scientific hunt, though any new program would face intense scrutiny and would presumably need to be better designed.

Judges said explicitly there was nothing in international law that forbids killing whales as part of a scientific study. It also noted that whales culled for scientific purposes may be slaughtered and sold — although that could not be the primary purpose of a scientific study.

Consumption of whale meat has declined in popularity in Japan in recent years but it is still considered a delicacy by some. Most of the whale meat from Japanese hunts ends up being sold.

Mitsumasa Kamiota, an official with Japan’s Fisheries Agency, underlined that Japan has not said it will quit research whaling altogether. He said Monday’s ruling only affects the country’s Antarctic program, and whaling in the north Pacific will continue.

Kamiota also hinted that Japan may eventually come up with a new research program in the Antarctic. He said Japan does not intend to withdraw from the International Whaling Commission.

"There is no change to our commitment to continue scientific research whaling under the international rules," he said. "We will carefully examine what is allowed and what is not allowed under the ruling."

Japan had argued that Australia’s suit was an attempt to force its cultural norms on Japan, saying it was equivalent to Hindus demanding an international ban on killing cows.

Associated Press reporters Mari Yamaguchi and Kristen Gelineau contributed to this story from Tokyo, Japan and Sydney, Australia.