US steel and aluminum producers jump as Trump plans additional import tariffs

** Shares of steel and aluminum manufacturers in the United States climb after President Donald Trump said he will introduce new 25% tariffs on all steel and aluminum imports into the U.S., on top of existing metal duties

** U.S. Steel X adds 7.1%, following on comments from Japan's Chief Cabinet Secretary Yoshimasa Hayashi that Nippon Steel 5401 is considering a bold change in buyout plan

** Among other steelmakers, Nucor NUE rise 3% and Steel Dynamics STLD

** Roughly a quarter of all steel used in the U.S. is imported, mostly from neighbours Mexico and Canada or close allies in Asia and Europe like Japan, South Korea and Germany

** Aluminum companies Century Aluminum CENX gain 8.8% and Alcoa AA up 5.1%

** Roughly half all aluminum used in the U.S. is imported, and the vast majority comes from Canada

** Asian and European peers fall