An international commission has recommended the southern bluefin tuna catch be halved in 2007 to prevent depletion of the species, sources said Tuesday.

If the tuna are caught at the ongoing pace, there is a 50 percent chance that all fish capable of laying eggs will be gone by 2030, according to a report not yet released by the Commission for the Conservation of Southern Bluefin Tuna. The commission consists of Australia, New Zealand, South Korea and Japan.

Fishing nations may have little choice but to accept the proposal partly because Australia is pushing hard for a substantial cut in the catch, the sources said. Japan's Fisheries Agency has said it has taken the commission's recommendations seriously.

Most southern bluefin tuna is shipped to Japan for consumption as premium sashimi.

The population of the species has remained at a record low level since 2000 and looks unlikely to start increasing anytime soon, the commission said.

If the fish population is to be maintained at the current level until 2014, the catch must be reduced to 7,770 tons.