Anti-whaling activists said Thursday there would be demonstrations in Tokyo and eight other cities around the world this weekend against Japan's hunt.

Protesters are expected to gather in the Japanese capital to call for an end to the annual state-sponsored whaling mission to the Southern Ocean, due to start in the next few weeks, and to the capture and slaughter of dolphins in the town of Taiji.

Action for Marine Mammals are planning to march through the commercial districts of Shibuya and Harajuku on Saturday, group spokesman Hideaki Nagai told AFP.

Demonstrations are planned on the same day in Canberra, London, Los Angeles, Miami, Milan, Sao Paulo, Vancouver, and a city in Texas, he said.

"We don't think whaling and dolphin-hunting are necessary in Japan, although we are not against indigenous people's rights to hunt marine mammals," he said.

"In particular, we think hunting wild dolphins to send them to aquariums is ethically problematic," he added.

Taiji, in the country's west, drew global attention after "The Cove", a hard-hitting film about the annual dolphin hunts there, won the Academy Award for best documentary in 2010.

Fishermen corral about 2,000 dolphins into a secluded bay, select a few dozen for sale to aquariums and slaughter the rest for meat. The dolphin hunt takes place over a period of months.

Japan hunts whales using a loophole in a global moratorium that allows killing the sea mammals for what it calls "scientific research", although the meat is later sold openly in shops and restaurants.