U.S. Trade Representative Robert B. Zoellick said yesterday that he strongly supported filing an international trade case against the European Union for its refusal to accept genetically modified food, throwing down a gauntlet on one of the touchiest issues in relations between the United States and Europe.

Zoellick's remarks, at a news conference in Washington, signaled that the United States is likely to bring suit against European governments in the World Trade Organization, perhaps within weeks. Such a suit, long favored by American farm and corporate interests and by lawmakers on Capitol Hill, would seek to overturn a moratorium on gene-altered plants, such as corn and soybeans, that was adopted by European governments four years ago during a consumer backlash against the crops.

A suit would be the Bush administration's strongest response to date to anti-biotechnology sentiment in Europe, and experts on both sides of the Atlantic regard the government's legal argument as compelling. "I tend to think the U.S. government probably has a pretty good case," said John H. Jackson, a specialist in international law at Georgetown University.

Yet there is concern in some quarters that a suit could stir up European public opinion against the United States -- and possibly even set off a wider trade war, prompting the European Union to impose sanctions in unrelated trade battles. And it is far from clear that even a successful legal case would open European markets to foods made with gene-altered crops, because resistance among European consumers is perceived to be overwhelming.

In essence, Zoellick would be arguing that anti-biotech rules in Europe are a response to unreasonable public fears, not to meaningful scientific research, and therefore represent trade discrimination against U.S. agricultural products. He said yesterday that he was deeply concerned that European resistance to the technology appears to be influencing the trade policies of other nations, even of African governments that have turned down genetically modified American grain meant for starving people.

"I don't see things getting improved," Zoellick said. "Instead I see something extremely disturbing: the European anti-scientific view spreading to other parts of the world -- not letting Africans eat food you and I eat, and instead letting people starve." He called this "immoral" and described the European view of biotechnology as "Luddite," a reference to the English workers who smashed machines to save their jobs at the beginning of the Industrial Revolution.

Zoellick's counterpart in the European Union, Pascal Lamy, told reporters yesterday that the issue should be settled through negotiation instead of litigation, adding that a trade suit would make finding a solution "more complex."

But he added: "If there was to be litigation, of course we would fight it, and I believe we would win it."

Genetically modified crops have become widespread in North America since the mid-1990s, accounting for half or more of the U.S. and Canadian acreage of some row crops. Generally, these plants have been altered in ways that help them resist insects or weeds. Gene-altered corn, soybeans and canola, or ingredients made from them, appear in a large majority of the products on American grocery shelves.

Though environmental groups oppose the crops, and some controversy lingers in this country, the Agriculture Department, the Food and Drug Administration, and the Environmental Protection Agency have declared the existing crops safe for human consumption and safe for the environment. American companies are working on many new varieties of gene-altered plants, including some that promise improved nutrition.

The situation in Europe is different. A series of food disasters there, involving problems such as "mad cow" disease being passed to humans through food, was followed in the late 1990s by a fierce controversy over genetic manipulation of crops. Nearly every European government adopted labeling laws and imposed moratoriums on the crops, costing U.S. farmers at least $300 million a year in export revenue.

U.S. interests contend that the European crackdown is not based on legitimate scientific concerns, as it must be under World Trade Organization rules, but simply on public fear. While acknowledging that they will never be able to force European consumers to buy foods they don't want, some American companies want to test whether consumer resistance across the Atlantic is really as strong as perceived.

"Biotech companies would be happy to have their products put to that kind of test," said Val Giddings, vice president of food and agriculture for the Biotechnology Industry Organization, a trade group in Washington. "Get trade barriers out of the way and see what consumers really do."

Trade Representative Zoellick said he sees "the European anti-scientific view spreading to other parts of the world -- not letting Africans eat food you and I eat." Pascal Lamy, the EU's trade commissioner, talks to reporters yesterday in Brussels. He said the food issue should be settled through negotiation.