European leaders vowed on Tuesday to retaliate after President Trump announced that he would raise tariffs on aluminum and steel to 25 percent, even as they held out hope for a potential deal that could stave off painful effects for a weakened economy.
European Union officials have argued that Europe and the United States are deeply intertwined and that igniting a trade war would hurt both sides. But they have also been quietly preparing to hit back against possible U.S. tariffs, and officials have said they are ready to enact countermeasures if no trade solution can be found.
“Unjustified tariffs on the E.U. will not go unanswered — they will trigger firm and proportionate countermeasures,” Ursula von der Leyen, the president of the European Commission, the European Union’s executive arm, said in a statement.
Maros Sefcovic, the E.U. commissioner charged with trade and economic security, told members of the European Parliament on Tuesday that the new U.S. tariffs were “a lose-lose scenario,” adding that the “time has come” for a European response.
“We are currently assessing the scope of the measures announced overnight and will be responding in a firm and proportionate way by counter measures,” he said.
The steel and aluminum tariffs are expected to go into effect March 12, leaving some time for possible negotiation.
Former President Joseph R. Biden Jr. had worked out an agreement with European leaders in 2021 that allowed specific amounts of steel and aluminum to enter the United States free of tariffs. The deal was extended in 2023 and was to stay in force until the end of this year.
According to the U.S. Commerce Department, the United States imported about four million metric tons of steel products and 283,000 metric tons of aluminum products from the European Union in 2022. Germany is the largest European exporter of steel to the United States, followed by Italy and Spain.
Europe is expected to tighten its safeguards for its domestic steel industry, but the timing of the response remained uncertain on Tuesday.
“We are not in a position yet to say exactly when we will be responding, very concretely,” Paula Pinho, the European Union’s chief spokeswoman, said during a news conference on Tuesday.
For Europe, the steel and aluminum tariffs are only the first shoe to drop. Mr. Trump has made it clear in recent days that he could announce more wide-ranging “reciprocal” tariffs as early as Tuesday. Those would most likely affect the European Union, potentially seeking to equalize tariff rates between the two economies on key products like cars.
For European Union automakers, the United States is the second most important market, after Britain.
“It seems likely that a reciprocal tariff would equalize auto tariffs — this would be aimed mainly at the E.U., which has a 10 percent tariff on cars,” economists at Goldman Sachs wrote in a research note on Tuesday. E.U. officials have already suggested that they might consider lowering tariffs on cars.
As it tries to negotiate, Europe finds itself in a different position from where it was when Mr. Trump ushered in higher tariffs in 2018, said Chad Bown, a senior fellow at the Peterson Institute for International Economics, who focuses on trade.
Both the war in Ukraine and a more aggressive stance coming from China have ramped up risks for Europe, and they have prodded officials to emphasize the importance of trans-Atlantic cooperation.
“It’s a very different position from where they were in the first administration,” Mr. Bown said.
“They may decide that: No, no, the United States is not a reliable partner here,” he said. But “they’re having to think of this as a much bigger set of issues — it’s not just trade and tariffs.”
Europe’s economy has also been growing more slowly, putting many of its member nations in a weaker spot heading into a possible trade war. The economy of the 20 countries using the euro currency was flat in the fourth quarter of 2024, after expanding just 0.4 percent in the previous quarter.
