Maritime New Zealand (MNZ) yesterday apportioned blame to the skippers of both the protest trimaran, Ady Gil, and Japanese whaling ship Shonan Maru No 2 following a collision in the Southern Ocean on January 6 which left the Ady Gil in two pieces.
Hours after the report was released in New Zealand, Japan's vice fisheries minister Takashi Shinohara told reporters: "Our position that the blame should be on Sea Shepherd and the Ady Gil, not on us, does not change at all."
"We cannot tolerate such a dangerous act," he said.
Japan has claimed that New Zealand captain Pete Bethune accelerated to put the Ady Gil in the path of the Shonan Maru II, while Sea Shepherd has said the whaler deliberately rammed the vessel, splitting it in two.
MNZ said the master of the Shonan Maru initially had responsibility for keeping his vessel clear of the Ady Gil, due to its position as the overtaking vessel.
"He had ample opportunity to avoid the close quarters situation that subsequently developed, but failed to do so".
But the report also found Ady Gil master Pete Bethune failed to respond by taking appropriate evasive action, "choosing instead to maintain his course and speed, which allowed the close quarters situation to develop into a collision risk".
It said tensions were high in the lead-up to the collision, with anti-whaling protesters on the Ady Gil having run an aggressive campaign against the whaling fleet, and the whalers also aggressively defending themselves.
"It's difficult for us to evaluate the New Zealand report," said a Japanese fisheries agency official, speaking on condition of anonymity.
"But the collision would never have occurred if they had not come out to commit acts of sabotage."
Japan hunts whales in southern waters around Antarctica, making use of a loophole in a 1986 international moratorium that allows "lethal research".
New Zealand Government officials said yesterday they were considering whether vessels which are not ice-strengthened -- such as the Ady Gil -- should be allowed to sail into Antarctic waters.
All NZ vessels -- and foreign vessels leaving NZ ports -- sailing into the Southern Ocean have to get environmental-impact approvals from the Ministry of Foreign Affairs and Trade, which has said it will consider whether the collision report raises new factors it needs to feed into the approval process.
And Maritime New Zealand (MNZ) director, Catherine Taylor, said that her office had under "active consideration" the issue of what vessels should be allowed to sail into Antarctic waters from NZ ports.
Pete Bethune, who was imprisoned in Japan for four months earlier this year after he boarded the Japanese whaler, said he was happy with most of the findings.
"The Shonan Maru 2 was the overtaking vessel and we had right of way," he said. "It's the equivalent of two cars approaching traffic lights and it was the Japanese who ran the red light."
