An international conference on managing Pacific bluefin tuna stocks has kicked off in Kushiro City, in Japan's northernmost prefecture of Hokkaido.

The conference started on Wednesday, and will last through next Tuesday.

Delegates from 13 countries and regions, such as Japan, the United States, South Korea and Taiwan, are taking part in the meeting.

Pacific bluefin tuna stocks declined considerably due mainly to overfishing, but are now recovering as a result of international management efforts.

At the conference, Japan is calling for expanding the catch quota of bluefin tuna in the western and central Pacific Ocean, including waters around Japan.

Japan is proposing a 130-percent increase in the quota for large bluefin tuna weighing 30 kilograms or more, and a 30 percent increase in the quota for those less than 30 kilograms.

Japan's fisheries minister Sakamoto Tetsushi sent the conference a video message saying that when efforts to manage stocks bear fruit, they should be rewarded. He said he strongly hopes for an agreement on appropriate measures for a quick, considerable recovery in the stocks.

But it remains to be seen whether the participants will reach an agreement, as some delegates are voicing concern about such large quota increases.