Ecologists fear that moves this week at the International Whaling Commission (IWC) in Monaco to resume commercial whaling in territorial waters and by tribal groups will lead to a sharp increase in hunting worldwide.
Greenpeace, the International Fund for Animal Welfare (IFAW) and the World Wildlife Fund (WWF) said in a statement to the IWC's 49th annual meeting that "whaling is growing rapidly and is out of the IWC's control".
The statement added: "Unless firm action is taken to bring the situation under control, unregulated whaling looks set to increase even further."
The environmental organisations have urged establishment of "a global ocean sanctuary" but are contesting a proposal by Ireland that whale hunting would be allowed to resume in coastal waters in exchange for the creation of a worldwide sanctuary in the remainder of the oceans.
The US government is backing a campaign to permit the Makah tribe in north-west Washington state to resume whale hunting for "cultural" reasons after a 70-year break. The Makah seek authorisation to take five grey whales a year provided the meat is not sold and argue the species is not under threat in the north-west Pacific.
Ecologists say the US proposal is deliberately misleading. It has encountered opposition within Congress, where 40 representatives warned the move would encourage illegal whale-hunting and objected to what they see as abandonment of the traditional US stance of protecting whales.
A Makah tribal spokesman, Mr Dave Sones, tried to explain the cultural and historical significance of hunting, saying it was an "honour to the species we hunt" and there was "long and documented respect" for the grey whale in Makah culture.
Ireland, which is to chair the commission for the next three years, will propose a limited resumption of commercial hunting. Ireland considers the number of whales being killed a "major problem" and hopes that allowing limited hunting will end abuse in the guise of hunting for "scientific" purposes, a concealed form of commercial whaling.
Japan, in particular, has been selling whale meat, earning 3.5 billion yen (about £23 million) in the 1996-1997 season, even though it says its whaling activities are for "research".
Norway has always rejected the moratorium, saying stocks of minke whales are sufficient to permit what Oslo says is limited culling.
Two weeks ago Britain said it was prepared to back the limited resumption of commercial whaling in coastal waters by Japan and Norway in return for their strict observance of an international ban elsewhere.
Britain's Agriculture and Fisheries Minister, Mr Elliot Morley, said London was considering supporting the Irish proposal since it would close a legal loophole under which whales were killed for "scientific purposes" while their meat found its way on to Norwegian and Japanese dining tables.
Norway has never signed on to the whaling moratorium of 1986 so it continues to hunt freely. Japan does the same, openly violating the Antarctica sanctuary for whales established in 1994.
A total of 1,043 whales has been slaughtered so far this year, compared with 383 in 1992. All this whaling is legal under current arrangements.
The Irish whaling commissioner, Mr Michael Canny, who is IWC vice-chairman, said Ireland did not want to legalise whaling but to regulate it.
"We are suggesting a very strict management scheme, including satellite tracking, DNA tracing of meat samples and a total ban on international trade in whale meat," he said.
The 33-member IWC has no powers to impose a whaling ban. There must be a consensus.
Japan failed yesterday to convince the IWC to make decisions by secret ballot, a procedural move that might have led to the easing of strict limits on whaling.
Nations which now oppose easing restrictions might shift positions if they could act anonymously, enabling them to escape criticism from global environmental groups and anti-whaling states.