Updated

An International Whaling Commission panel says Japan's revised plan for research whaling in the Antarctic still lacks a convincing explanation of why it needs to kill the mammals.

Commercial whaling was banned by the commission in 1986, but Japan has continued to kill whales under an exemption for scientific research. However, the International Court of Justice ruled last year that the hunts were not truly scientific.

Following the ruling, Japan submitted a revised proposal last November for the upcoming Antarctic whaling season in which it scaled down its catch quota to about one-third the level of previous years.

Japanese fisheries officials said Monday they are open to revisions but are not planning any major changes to the new plan.