The move, which follows the bitter dispute over European banana imports, comes into effect on 15 June, and now includes American beef that is being sold as "hormone-free".
Most US beef is already banned from Europe because of safety fears over the use of hormones which are widely used to stimulate growth in cattle. That restriction is highly controversial, and the World Trade Organisation has ordered its removal, unless the EU can prove that eating US beef is unsafe.
Yesterday's widening of the trade embargo, ordered by the EU's standing veterinary committee, follows scientific tests which showed that 12 per cent of supposedly hormone-free US beef contained hormone residues.
The British Government last night attacked the EU decision, arguing that the ban was unnecessary because there was no evidence of a genuine health risk from the American meat.
A British official said: "We are concerned about the shortcomings in the US control systems which the test findings showed up [and] we are glad that the US is taking them seriously. But given that the analysis showed that the residual level of hormones were below the minimum human risk level, we believe that the Commission's proposals are disproportionate."
The EU imports between 7,000 and 8,000 tons of US hormone-free beef a year, which is worth around $20m (pounds 12.5m) and is marketed as high-quality meat. But with a final settlement of the high-profile transatlantic row over the EU's banana import regime still not reached, there is concern that the decision could worsen the diplomatic climate.
In London yesterday Lord Young of Graffham, the former Conservative trade minister, warned that the world could be plunged into a global depression if the simmering trade war escalates out of control.
Addressing the annual convention of the Institute of Directors, he said there was a new "crisis" looming over the hormone-treated beef. There was a danger, he added, of Europe being seen by the US as a "Fortress Europe for Food" .
Later, Philip Lader, the US Ambassador in London, sought to play down the tensions. He acknowledged that there were "significant differences" dividing the US and Europe and said his aim was to "lower the decibel level". Last month Mr Lader was given a dressing down by the Secretary of State for Trade and Industry, Stephen Byers over the 100 per cent tariffs imposed by the US on British goods such as cashmere sweaters and batteries.
After yesterday's ruling in Brussels , the acting European agriculture commissioner, Franz Fischler, said he is "ready to work closely with the US authorities to resolve this problem". But Mr Fischler added that yesterday's decision can only be reversed when the EU is satisfied that America's beef exports to Europe have been produced without the use of hormones.
The commission said that, until the ban comes into force on 15 June, EU member states should increase to 100 per cent their checks on imports of US beef and bovine liver imports. Commission officials stressed there was still a possibility of averting the ban, if the EU and the US could agree on a way of monitoring its hormone-free beef before 15 June.