Japan will go ahead with its annual whale hunt in Antarctica while boosting security to guard against possible harassment by environmental protesters, the agriculture and fisheries minister said Tuesday.

"Japan will conduct the research whaling while strengthening measures against acts of sabotage, including dispatching Fisheries Agency escort ships," said Agriculture, Forestry and Fisheries Minister Michihiko Kano.

In February, Japan for the first time cut short its Antarctic fleet mission for the 2010-2011 season by one month, when it had taken only one fifth of its planned catch, citing interference from Sea Shepherd's vessels.

The US-based Sea Shepherd, which says its tactics are non-violent but aggressive, hurled paint and stink bombs at whaling ships, snared their propellers, and moved its own boats between harpoon ships and their prey.

Since cutting short its whaling operation, Japan has studied whether the country should continue what it calls "scientific research" for the 2011-2012 season.

The government-affiliated Institute of Cetacean Research has organised such operations since 1987, citing a loophole in a 1986 international moratorium on commercial whaling that allows hunts for scientific research.

Anti-whaling nations and environmentalist groups condemn the activity as a cover for commercial whaling but Japan said it is necessary to substantiate its view that there is a robust whale population in the world.

Kano said at a news conference: "Japan intends to pursue the resumption of commercial whaling. For that purpose, Japan needs to continue research whaling."

The founder and head of Sea Shepherd Conservation Society, Paul Watson, told AFP in July that he would continue harassing Japanese whalers if they returned to the Antarctic sanctuary.