The US and Britain are extending their ban on imports of metals produced in Russia, due to the Russian war against Ukraine. Aluminium, copper and nickel produced in Russia after April 13 will no longer be traded on the world’s two largest metal exchanges in London and Chicago, the US and British treasury departments announced overnight on Friday night. This would exclude Russian metal producers from the profits of the London Metal Exchange and the Chicago Mercantile Exchange and reduce an important source of income for the Kremlin to finance its war in Ukraine. The joint action by the two coun…