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PARIS, March 2 (Reuters) - Europe will retaliate with a firm joint response if the Trump administration goes ahead with "unacceptable" tariffs on imported steel and aluminum, French Finance Minister Bruno Le Maire said on Friday.
Le Maire said that "all options are on the table" including retaliation before the World Trade Organisation and countermeasures to limit European imports of U.S. goods.
"The United States needs to know that if it goes ahead with these measures, they will meet with a strong, coordinated and united response from the European Union," Le Maire told journalists at the ministry.
"These unilateral measures are not acceptable. They would have a major impact on the European economy and French companies like Vallourec and Arcelor," Le Maire said, referring to Luxembourg-based European steel producer ArcelorMittal.
U.S. President Donald Trump said on Thursday he would formally announce next week duties of 25 percent on steel and 10 percent on aluminum although White House officials later said some details still needed to be ironed out.
Trump believes the tariffs will safeguard American jobs, but many economists say the impact of price increases for users of steel and aluminum, such as the auto and oil industries, will destroy more jobs than curbs on imports create.
Le Maire said Europe and the United States needed to jointly tackle the problem of some countries heavily subsidising their producers, which makes it possible to dump their products abroad at prices below the cost of production.
"A trade war between Europe and the United States will only have losers," Le Maire said, adding that he would call his German and British counterparts on Friday to discuss the matter. (Reporting by Myriam Rivet; writing by Leigh Thomas; editing by Michel Rose and Sarah White)