Russia and other countries bordering the Caspian Sea say they've agreed to stop fishing black-caviar-producing sturgeon because the fish is close to extinction.

Russia's Federal Fisheries Agency announced the ban, also agreed to by Kazakhstan, Iran, Azerbaijan and Turkmenistan, will begin Jan. 1 for one year and may be extended for as long as five years, RIA Novosti reported Friday.

Female sturgeon, including the prized beluga, are among the world's most valuable fish and are harvested for their black caviar roe, which can sell internationally for $70 an ounce.

The Caspian Sea provides more than 90 percent of the world's annual sturgeon catch, but overfishing after the collapse of the Soviet Union has reportedly decimated the species.

Even with the ban repopulation would be slow because female sturgeon can take decades to reach sexual maturity.

Russia had already banned commercial sturgeon fishing in the Caspian in 2002, but has been still permitting a minimal annual catch.