WASHINGTON, April 3 --  US President Donald Trump yesterday ordered new tariffs on certain medicines, alongside an overhaul of metal duties, doubling down on his trade agenda a year after unleashing trade wars on virtually all partners.

The latest pair of orders he signed pile pressure on pharmaceutical companies to manufacture more in the United States, while separately targeting firms that officials accuse of "artificially manipulating" metals prices.

Finished products containing substantial amounts of steel, aluminum and copper will also face a lower 25-per cent tariff on their full value instead of being targeted for the amount of metals they contain, a move to simplify an onerous system for firms.

It is not immediately c...