TOKYO--Japan said Tuesday it plans to ask Australia and possibly New Zealand and Chile to ban an anti-whaling protest ship from using their ports to refuel, heightening a cat-and-mouse game in Antarctic waters between Japan's whaling fleet and the conservationists.

The Sea Shepherd group has said its anti-whaling ship, the Steve Irwin, has left pursuit of Japan's whaling fleet after chasing it for 2,000 miles (3,200 kilometers) and is now headed to port to refuel. It suggested on its web site it will seek a port call in Australia, but has not provided further details.

Japan, which considers the actions of the Steve Irwin to be tantamount to piracy, reacted Tuesday by saying it will ask countries where the ship might make port calls to refuse it entry.

"We are going to request a port closure against it," Foreign Ministry official Chiharu Tsuruoka said. "They have obstructed our activities in the past, and their action is extremely dangerous. They are like pirates."

Tsuruoka said Tokyo has not made such a request yet because it is not clear where the Steve Irwin will go. He said the possibilities have been limited down to Australia, New Zealand and Chile.

The Steve Irwin's captain, Paul Watson, said he intended to dock in Australia to challenge that country's support for his efforts despite the Japanese pressure for a port closure.

"After chasing the Japanese whaling fleet for over 2,000 miles, the Sea Shepherd Conservation Society ship Steve Irwin must return to port for fuel," the group said on its web site Sunday.

"Although the ship is as close to Puntarenas, Chile as it is to Hobart, Tasmania and even closer to Dunedin, New Zealand, Capt. Paul Watson has decided that the ship will return to Australia."

Last year an Australian customs ship tracked the Japanese fleet in the Antarctic Ocean, gathering evidence for a possible legal battle against whaling.

Japan has temporarily suspended its whale hunt in Antarctic waters after a crewman apparently fell overboard from one of the vessels in the six-ship whaling fleet. The accident was not believed related to the Sea Shepherd protests.

The Japanese fleet plans to harvest up to 935 minke whales and 50 fin whales this year. Under International Whaling Commission rules, the mammals may be killed for research but not for commercial purposes. Opponents say the Japanese research expeditions are a cover for commercial whaling, which was banned in 1986.

Last month, the whaling fleet came under attack by the Sea Shepherd when activists lobbed 25 bottles of rotten butter at the fleet in protest of the whale harvest. They have denied Japanese assertions that the Steve Irwin rammed a Japanese ship.