Japan may pull out of the International Whaling Commission in response to what it sees as the hijacking of the commission by antiwhaling nations, the chief Japanese delegate to the IWC's annual meeting suggested Thursday.

Minoru Morimoto made the threat at a news conference after the IWC closed an acrimonious four-day meeting in which Japan lost several key votes for its whaling programs.

Morimoto said Japan will consider whether to review its relationship with the IWC. "We have a number of options," he said.