Japan has condemned an attack on its whaling fleet and says it will raise the incident at this week's meeting of the International Whaling Commission.

The conservation group, Sea Shepherd, has confirmed protesters threw more than 20 bottles and packets of substances onto the Japanese whaling ship, the Nisshan Maru.

Japan says four people were injured as a result of the attack.

But the Sea Shepherd's Paul Watson maintains the substances thrown were not toxic.

"We certainly didn't injure anybody because we saw where every container hit," he said.

"It was fully video-taped.

The Japanese video-taped it and I'm sure that if we had have hit somebody they'd have it on their website, which they do not have.

"My understanding is that the three injuries were three guys who got sick from the smell and just threw up."

International Whaling Commission meeting
Japan will seek to raise the issue when members of the International Whaling Commission (IWC) start an informal three-day meeting in London on Thursday.

The London meeting was arranged by the US commissioner to the IWC, William Hogarth, in a bid to break a bitter deadlock between its pro- and anti-whaling groups.

Mr Hogarth, the current IWC chairman, helped persuade Japan last year as a goodwill gesture to suspend its plans to kill humpback whales for the first time in four decades.

Japan, which says whaling is part of its culture, kills up to 1,000 whales a year using a loophole in a 1986 global moratorium that allows "lethal research" on the giant mammals. The meat then goes onto dinner plates.

Australia, Japan discuss protest action

Australia has also condemned the attack, but has denied its ambassador has been formally summoned over the protest in the Southern Ocean.

The foreign affairs department in Canberra says, however, that discussions have occurred between Australian and Japanese officials.

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