Australia says it intends to send planes and a customs ship to monitor Japanese whalers off Antarctica. The government says the surveillance mission will collect video and other evidence that could be used in any legal action aimed at stopping Japan's whaling program, which Tokyo insists is only for scientific research. From Sydney, Phil Mercer reports.

A crew of Japanese whaling vessel Yushin Maru waves upon departure for a hunt at a port of Shimonoseki, southwestern Japan (File)

The Japanese say their annual whale hunt, which has been increased again this year, is purely for scientific research. Anti-whaling activists, along with a number of governments, are not buying it.

Now Australia's new foreign minister, Stephen Smith, has stated bluntly and loudly what others have been saying for years: this is a case of the slaughter of whales, and not scientific research.

The Australians say they are sending an unarmed ship to shadow Japan's whaling fleet in the Southern Ocean this hunting season. Aerial patrols will also take part in the surveillance.

The government says any evidence it gathers could be used to mount an international court challenge against Japanese whaling.

In addition, Canberra says it will lead a group of anti-whaling nations in lodging a formal protest with the Japanese authorities within the next few days.

Foreign Minister Smith says the government intends to keep up the pressure on Tokyo.

"We will up our activity in the International Whaling Commission to seek to use our voice in the International Whaling Commission to bring an end to the so-called 'scientific whaling,'" he said. " The government is considering pursuing international legal action against the Japanese whaling."

In 2005, Japan more than doubled the size of its annual catch, to 935 minke whales. This season it says it also plans to catch 50 fin whales and - for the first time in 40 years - its hunters will also target 50 humpbacks.

The Japanese fleet set sail for Antarctic waters in mid-November, even as the United States, Britain, Australia and New Zealand denounced the increased quotas.

Environmentalists have welcomed Australia's decision to increase surveillance of the whale hunt. Steve Shallhorn of Greenpeace says the government's stance will put added pressure on Tokyo.

"It will send a very strong message to Japan that Australia and Australians are very concerned about continued illegal whaling in the Southern Ocean whaling sanctuary," he said.

Greenpeace says it will also continue it program of harassing the Japanese whalers. The Greenpeace ship Esperanza has left the New Zealand city of Auckland for Antarctic waters. Its crew says it is determined to find the Japanese fleet and disrupt its activities, as Greenpeace members did last year.