US President Donald Trump said Tuesday that upcoming tariffs on imported pharmaceuticals could go as high as 250 percent -- after starting at a lower level -- adding he plans to unveil fresh duties on foreign semiconductors.

President Donald Trump said on Tuesday that the United States would initially place a "small tariff" on pharmaceutical imports before hiking it to 150% within 18 months and eventually to 250% in an effort to boost domestic production.

The Swiss president will fly to Washington on Tuesday to “present a more attractive offer” on trade to the US government, following Donald Trump’s decision to hit the country with steep tariffs. Karin Keller-Sutter will fly for “short notice” meetings with US officials “with a view to improving the tariff situation for Switzerland”,

President Trump's 39% tariff on goods from Switzerland is among the world's steepest import taxes. For the European nation, the announcement comes at an unwelcome time.

Canada said it was hopeful it can still strike a deal with the US to bring down its tariff rate even as the Trump administration denied that the high levies it set on America’s trading partners were up for negotiation.