Two South Korean steelmakers said they were considering new investment options in the United States, while Europe's steel mills warned of a flood of surplus metal as increased tariffs on U.S. steel and aluminium imports came into force on Wednesday.

President Trump imposed a 25 percent tariff on metal imports, sparking new global trade spats as he attempts to shield the U.S. economy from foreign competition.

Trump’s 2018 metals tariffs created job growth in the steel industry, but ultimately cost consumers more money as a result of job losses in industries that rely on steel and aluminum, studies have shown.