The IWC - the international body that regulates whaling - will gather for its annual meeting next week in Agadir, Morocco. The meeting is expected to seek a compromise between pro- and anti-whaling countries, which may include allowing commercial whaling on a limited scale.
A moratorium has been in place for 25 years, but countries such as Japan, Norway and Iceland hunt whales under a variety of exceptions to the ban. An IWC proposal was circulated in April to allow limited commercial hunts for 10 years.
Japan has frequently threatened to pull out of the IWC in the past. Agriculture, Forestry and Fisheries Minister Masahiko Yamada was asked Tuesday if Tokyo would quit the IWC if progress was not made toward easing the ban on commercial whaling.
"I am considering various options," Yamada said. "This is really the final stage, and we're not sure how things are going to turn out."
The proposal to allow commercial whaling has drawn criticism from all sides and drawn fresh attention to the whaling issue. The foreign minister of New Zealand and Australia's environment minister are due to attend next week's meeting.
Yamada said he would not attend, citing budget concerns. An official from Japan's foreign ministry said its representatives to the meeting had not yet been decided.
"This is one of the most important meetings of the IWC in the last 30 years. It is my sincere hope that all member nations come to this meeting determined to break the gridlock that has been a hallmark of the Commission for so long," Australian Environment Minister Peter Garrett said in a statement.
Anti-whaling states, including Australia and New Zealand, have called a proposed whaling quota system unacceptable and demanded an end to Japan's hunt in Antarctic waters.
Japan's whaling program includes large-scale scientific expeditions to the Antarctic, while other whaling countries mostly stay along their coasts. Opponents call Japan's scientific research hunts a cover for commercial whaling.
Australia is taking Japan to the International Court of Justice in a bid to stop Japanese whaling for scientific research purposes.
Yamada's comments were the first he made to reporters since assuming his post a week ago. He was one of several Cabinet ministers appointed by new Japanese Prime Minister Naoto Kan.