The U.S. government said this week it supports such a ban because evidence indicates the adult population of bluefin tuna has plummeted during the last half-decade, The Washington Post reported Friday.
Japan, which consumes roughly 75 percent of the world's annual bluefin catch, said Thursday that it would not comply with such a ban, scheduled to be considered this month when representatives from 175 countries meet in Doha, Qatar.
For years, Japan exceeded its bluefin quoto but recently reduced its catch substantially. Government officials said they believe they have done enough to help ensure the bluefin's survival.
"If worst comes to worst, Japan will have no choice but to lodge its reservations," said Masahiko Yamada, a Japanese vice minister for fisheries. "Since the United States has made its position clear, it has become tough for Japan."
Data indicate the adult population of eastern Atlantic and Mediterranean bluefin plunged 74 percent in 50 years, much of it in the past decade, the Post said. In the western Atlantic, the population has fallen 82 percent. Many marine scientists said scientific data justify a total ban.
When the representatives meet in Doha, they will vote on measures to protect bluefin tuna and other species found to be at risk under the Convention on International Trade in Endangered Special of Wild Fauna and Flora, the Post said. A two-thirds majority is needed to impose a ban.