Belgium and Russia banned the import of vegetables from Spain, believed to be the source of at least some of the contaminated cucumbers. Madrid shot back saying it would seek financial compensation from the European Union for lost sales.
More than two weeks after the food poisoning outbreak was first reported in northern Germany, the number of confirmed and suspected cases has reached 1,200, according to media reports.
The Robert Koch Institute (RKI), Germany's national disease institute, said three deaths have been officially linked to the bacteria, but "in total about a dozen people have died according to regional authorities".
These authorities later Monday announced two more deaths: a woman of 50 and a man of 75 -- bringing the toll to at least 14.
The Stockholm-based European Centre for Disease Prevention and Control has described the outbreak of the strain of E. coli as "one of the largest worldwide and the largest ever reported in Germany".
Authorities in Germany warned against eating raw vegetables after traces of the bacteria were found on organic cucumbers from Spain last week.
But officials said they are unsure what caused the sudden outbreak of enterohaemorrhagic E. coli (EHEC) which can result in full-blown haemolytic uraemic syndrome (HUS), a disease that causes bloody diarrhoea and serious liver damage and possible death.
The outbreak has hit countries including Britain, Denmark, Sweden and the Netherlands, but most these cases appear to involve people who had recently travelled to or from Germany.
"Normally we see about 1,000 cases per year, but we've now had some 1,200 cases in just 10 days," Jan Galle, director of the Luedenscheid clinic in western Germany, told ZDF public television.
"And we know that this time the EHEC strain is especially virulent and resistant, and has led to a very high number of HUS" cases, he added.
RKI has reported 329 confirmed HUS cases nationwide.
"Rapid identification of potential cases linked to this outbreak, within Germany or among persons who have travelled to Germany since the beginning of May, is essential to prevent the development of severe disease," the European disease control centre said in a statement Monday.
German Consumer Affairs Minister Ilse Aigner held emergency talks with Health Minister Daniel Bahr and regional state representatives, telling reporters the crisis has "taken a European dimension".
Burger said the source of the contamination had not been definitively identified.
Last week his organisation said a study had shown that all those affected had eaten significantly above-average amounts of tomatoes, lettuce and cucumbers.
European health officials said there was currently no indication that raw milk or meat is associated with the outbreak.
Many German supermarkets and shops removed all Spanish-grown vegetables from their shelves.
Spain in turn has hotly denied that its cucumbers were the cause of the outbreak and said it would seek compensation from the European Union for the "enormous damage" to its agriculture industry.
Belgium said it was blocking cucumber imports from Spain, while Russia said it was banning vegetable imports from both Spain and Germany.
The Netherlands, which usually exports vast amounts of vegetables to Germany, said sales had collapsed. German farmers also said consumers were boycotting their vegetables.
Doctors remained unsure how to treat the disease which can result in total kidney failure.
"We have 61 adults hospitalised, 21 in intensive care," a spokeswoman for the Eppendorf University Clinic in Hamburg, where most cases are being treated clinic, said Monday evening.
The clinic has appealed for blood donations.
"We are using between 500 and 700 bags of plasma per day, compared to 60 normally. We're running out of supplies," the spokeswoman said.
Rolf Stahl, a neurologist at the clinic, said nearly a third of patients there had lost all kidney functions and were on dialysis.
Doctors were experimenting with a new type of monoclonal antibodies drug, Eculizumab, which, while not officially approved, has been administered to 11 patients in a bid to save their lives.
"The infection source remains active and we have to reckon with a growing number of cases," Bahr said.