Militant anti-whaling campaigners said Wednesday they had launched a new "Godzilla" speedboat to chase Japanese harpooners hunting the giant mammals in Antarctic waters.
The Sea Shepherd Conservation Society this week unveiled its newest vessel "Gojira", as the giant monster Godzilla is known in Japan, some 11 months after its futuristic Ady Gil craft was lost in a high-seas clash with whalers.
The Australia-flagged 33-metre (100-foot) stabilised monohull is imposing without being overly heavy, and will be fast enough to chase the Japanese, the group's Australian director Jeff Hansen said.
"We are not going to release the speed (it can reach), we are just saying that it is going to go faster than a harpoon ship," he told AFP.
"This vessel is purely to be used for its speed advantage."
The black Gojira, which previously completed a round-the-world voyage in less than 80 days under the name Cable & Wireless Adventure, will join veteran Sea Shepherd ships the Bob Barker and the Steve Irwin on their annual southern hemisphere summer pursuit of the Japanese whalers.
Hansen said the two larger boats would leave Tasmania on Thursday, with the Gojira catching up with them several days later.
Sea Shepherd believes its activists will be leaving on the annual mission -- which usually extends until about March -- ahead of the Japanese boats for the first time ever.
"We're in a very, very good position right now," Hansen said. "We're the best prepared we've ever been."
Tensions ran high last season after a January 6 collision with a Japanese harpoon ship sliced off the front of the Ady Gil, a New Zealand-flagged trimaran.
A New Zealand inquiry found both vessels were at fault over the incident, which occurred as Sea Shepherd boats harassed Japanese harpooners and resulted in the Ady Gil sinking.
Hansen said Sea Shepherd had learned valuable lessons from the experience, adding that he hoped having an Australia-flagged ship involved in the campaign would push more action from Canberra on saving the whales.
Australia strongly opposes Japan's whaling and has started action against Tokyo in the International Court of Justice over its continued slaughter of the animals.
Japan hunts whales in southern waters around Antarctica using a loophole in a 1986 international moratorium that allows "lethal research", but does not hide the fact that the meat is later sold in shops and restaurants.
Explore further: Whalers, activists clash again off Antarctica