Another likely reason for caution is that the commission, the European Union’s executive body, has come under intense pressure to coordinate hundreds of millions of dollars’ worth of compensation to farmers for losses incurred on produce they had to take off the market after Spanish cucumbers were wrongly identified as a likely source of the outbreak in Germany.

Over the weekend a British seed company, Thompson & Morgan, rejected responsibility for the outbreak after a French official said that the sprouts used in the gazpacho were from seeds supplied by the company.

“We note that the French outbreak was localized to a specific event, which would indicate to us that something local in the Bordeaux area, or the way the product has been handled and grown, is responsible for the incident rather than our seeds,” the statement said.

The company said it was cooperating with the British health authorities.

Richard Howitt, a British member of the European Parliament, warned the French authorities against blaming the company, which is in his constituency, without definitive proof. Mr. Howitt said seeds for the sprouts could have picked up bacteria in Italy, where the company had sourced them. He also said that the French should be held responsible for any damage to the vegetable and salad markets in Britain if the company was not to blame.

In Britain, the Food Standards Agency said Saturday that no cases of food poisoning had been reported there that were linked to the outbreak in France. But it warned that sprouted seeds — including alfalfa, mung beans and fenugreek — “should only be eaten if they have been cooked thoroughly until steaming-hot throughout.”

The Food Safety Authority of Ireland warned that “consumers should not eat raw bean sprouts or other sprouted seeds, and caterers should not serve raw bean sprouts or other sprouted seeds.” The Irish authority also warned of “the possibility that contaminated seeds are on the market,” and it said that if “those seeds are still in circulation, other outbreaks could occur.”

The outbreak of E. coli is one of the deadliest to affect Europe in recent years, though it abated in Germany after the health authorities located its main source: sprouts grown on an organic farm in Lower Saxony in northern Germany.