In March, Trump imposed a 25% tariff on steel imports and a 10% tariff on aluminium, but granted temporary exemptions to the EU, Canada, Mexico, Brazil, Australia and Argentina.
The Trump administration announced that the U.S will impose tariffs on steel, aluminum imports from Europe, Canada and Mexico, as a previously designated exemption expires tonight at midnight.
More details to follow ...
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"It's not everyone attacking the other and we see who remains standing at the end", he said, declaring that the stiff taxes would be "unjustified, unjustifiable and dangerous".
EU Trade Commissioner Cecilia Malmstrom and Japanese Economy Minister Hiroshige Seko on Thursday warned against such a measure, saying it would cause "serious turmoil in the global markets".
Thursday's action also is expected to complicate USA efforts to confront China over a range of trade practices that the administration regards as unfair.
He cited a lack of progress in the renegotiations of the North American free-trade agreement as a reason for President Donald Trump eliminating an exemption Canada was given when worldwide tariffs were announced earlier this year.More news: Israeli hits dozens of Gaza targets after Palestinian mortar barrage
European and USA equities lost ground slightly on fears the United States measures could spark a trade war. The two sources briefed on the matter said the announcement was planned for the morning in Washington but that the timing could still change.
The EU has vowed to hit back at the U.S. with tariffs on American goods, including iconic items such as Harley-Davidson motorbikes, blue jeans and bourbon whiskey.
Tariffs on steel and aluminum imports to the US can help local producers of the metals by making foreign products more expensive.
While not confirming directly that the US would decide to impose tariffs, he said: 'It's up to the European Union to decide if it wants to take retaliatory measures.
Ross also said the European Union was unwilling to speak about renegotiating trade deals until the Trump administration threatened them with tariffs.
The U.S. plan has raised the threat of retaliation from Europe and fears of a global trade war - a prospect that is already weighing on investor confidence and could hinder the global economic upturn. "We continue to work closely with our European Union partners and will consider carefully the EU's proposals in response".
French Finance Minister Bruno Le Maire pledged that the European response would be "united and firm". "It's not that we can't talk just because there's tariffs", he said.
"We would operate within (multilateral) frameworks if we were convinced that people would move quickly", he said.