Key Points:

A collision between a Japanese whaler and an anti-whaling protest ship in frigid Antarctic waters has sparked renewed calls for the New Zealand and Australian Governments to block the Steve Irwin from refuelling in the two countries.

The Sea Shepherd conservation group ship Steve Irwin was trying to prevent the transfer of a dead whale up the slipway of the factory ship Nisshin Maru yesterday morning when the Japanese harpoon vessel tried to block it, making the collision unavoidable, said Steve Irwin captain Paul Watson.

No one was injured in the collision, which caused minor damage to the stern of the Japanese ship, the hardline anti-whaling group said.

But Japanese authorities said it was an "act of violence and unforgivable".

"It could have been much worse, people could have been killed," New Zealand based spokesman for the Institute of Cetacean Research Glen Inwood said.

Japan repeated a call for the two Governments to show responsibility for safety at sea and block the Dutch ship from ports in Australasia, he said.

Mr Inwood said the Steven Irwin would run out of fuel shortly and have to head back to either New Zealand or Australia to restock.

The Netherlands Government should also order the Dutch-flagged Steve Irwin to stop its criminal activities interfering with legal whaling operations, Mr Inwood said.

Although Japan officially stopped whaling under a 1986 global moratorium, it continues to take hundreds of whales under a loophole allowing whaling for research purposes.