Japanese whalers have asked a U.S. federal court judge in Seattle to order the Sea Shepherd Conservation Society to stop disrupting its whaling activities in the Southern Ocean surrounding Antarctica.

The Tokyo-based Institute of Cetacean Research and others are seeking a U.S. court order to prevent the anti-whaling Sea Shepherd and its founder from engaging in activities at sea that could harm the crew and damage its vessels.

But U.S. District Court Judge Richard A. Jones has delayed hearing the institute's motion for a preliminary injunction by several weeks, granting a Sea Shepherd request for more time to respond. The judge set a hearing for Feb. 16.

"The violence and attacks from the Sea Shepherd have increased year by year," the institute's spokesman Gavin Carter in Washington, D.C., said Tuesday.

The Japanese companies had hoped to resolve the issue of maritime safety diplomatically, he said, but decided suing was the best course after its last whaling season was cut short by interference from protesters.