Japanese whalers have told Australia's anti-whaling Environment Minister Ian Campbell to come clean about his ties to the provocative conservation group Sea Shepherd.

The Japan Whaling Association (JWA), which describes itself as a body which promotes and protects Japan's whaling culture, has been angered by the closeness of Senator Campbell and Sea Shepherd, which has a history of sometimes violent clashes at sea with whaling and fishing vessels.

Senator Campbell has reportedly offered Australia's Antarctic bases to the Sea Shepherd crew in the event of an emergency as the group's ships Farley Mowat and The Leviathan take on the Japanese whaling fleet in Antarctic waters this year.

The organisation makes clear it does not go to Antarctica to protest against whaling, rather it goes there to intervene with the purpose of upholding international laws protecting the whales.

Sea Shepherd leader Captain Paul Watson has referred to the Japanese whalers as criminals.

JWA president Keiichi Nakajima said Sea Shepherd posted on its website details of a conversation between its leader Captain Paul Watson and Senator Campbell who told Sea Shepherd he supported its efforts to oppose Japanese whalers.

"He apparently also assured Watson that in the event of emergency that Sea Shepherd could contact the Australian Antarctic bases for support," Mr Nakajima said in a statement.

"This is a massive u-turn by Senator Campbell. He's showing his contempt for international law and the International Whaling Commission (IWC).

"If he's got the support of his government, the problem is more serious."

Mr Nakajima recalled that last year, during confrontations in the Southern Ocean, Senator Campbell described Sea Shepherd's tactics as incredibly counterproductive.

"Obviously Mr Campbell has had a change of mind and finds approval in Sea Shepherd's actions," he said.

Mr Nakajima said that, at the IWC's annual meeting in St Kitts and Nevis this year, Australia had co-sponsored a resolution aimed at both Sea Shepherd and Greenpeace campaigns in the Antarctic.

"The resolution demands that contracting IWC governments not condone any actions that are a risk to human life and property in relation to research whaling and urges persons and entities to refrain from such acts," he said.

"Furthermore, the resolution encourages IWC member countries to ensure that the substance and spirit of this resolution are observed both domestically and internationally.

"Ian Campbell has taken this resolution, and thrown it out the window.

"In one move, he's shown his contempt for the IWC and for international law, and thrown his support behind illegal actions and eco-terrorism."

Captain Watson, in an interview with the British newspaper The Guardian, said he expected much more confrontation in the Antarctic this summer than last.

"Our objective is to place ourselves in harm's way to protect the whales," he told the paper.

"We recognise [the Japanese fleet] as a criminal operation and criminal operations are dealt with by aggressive intervention.

"This is a clear case of justifiable intervention against a criminal operation."

The Humane Society International says the Japanese have killed 1,253 minke whales and nine fin whales in Australia's self-proclaimed Antarctic Whale Sanctuary since 2001.