The country admitted yesterday that this year's hunt - which was due to take 945 whales by mid-March - will probably have to be abandoned as a result of a fire which has crippled its fleet's mother ship, the Nisshin Maru, and raised fears of an oil spill into the area's pristine waters.

Environmentalists hope that the 8,000-tonne ship, the only one capable of processing harpooned whales, will have to be scrapped altogether following what is its second serious fire in less than a decade. If so, they hope it will not be replaced - spelling an end to an annual hunt which has caused protests for a quarter of a century.

With neat irony, the crisis began as Japan was hosting a meeting of prowhaling members of the International Whaling Commission to work out a strategy for legalising a full return to the slaughter. Commercial whaling was banned after the commission agreed a moratorium in 1982, but Japan continued under the guise of scientific research.

The fire broke out on Thursday on the vessel's second deck, close to where the whales are processed, and has raged for days, partly fuelled by whale oil from the slaughtered mammals. One crew member was killed and most of the 148 others abandoned ship.

Environmentalists feared that some 330,000 gallons of oil aboard the ship could leak and be carried by currents to the Cape. The Norwegian government says it is "imperative" that the stricken ship is moved further away from Antarctica. But Japan has rejected help from the nearest boat best equipped to tow it, the Greenpeace protest ship Esperanza, a former tug.

The Japan Fisheries Agency said assistance was refused because the Greenpeace protestors are "environmental terrorists".