The nation’s Institute of Cetacean Research (ICR) has filed briefs in the U.S. District Court in Seattle stating its intent to resume whale hunting in the Southern Ocean as early as fiscal 2015.

The move, made Friday, immediately faced strong opposition from conservation group Sea Shepherd as it came less than two weeks after the International Court of Justice ordered Japan on March 31 to halt its so-called research whaling.

The government plans to resume whale hunting as soon as the fiscal year starting April 2015 by tweaking parts of its research program, including reducing the number of whales taken.

The ICR has said that the new program will not run counter to the ICJ ruling.

The ICR and Sea Shepherd have been locked in a legal dispute in the United States, with the institute seeking an end to the anti-whaling group’s interference in its hunt.

“The statement that Japan issued that they would comply with the ICJ ruling was I believe insincere,” Sea Shepherd founder Paul Watson said.

“Japan has a history of duplicity with regard to whaling. I fully expect that Sea Shepherd Global will be prepared to return to the Southern Ocean in December 2015 to once again defend the integrity of the Southern Ocean Whale Sanctuary,” Watson said.