The government said it was "disappointed" and would decide how to proceed after Trump on Friday set a 39 per cent tariff on the export-reliant country - more than double the 15 per cent rate for most European Union imports into the United States.
The levy - up from an originally proposed 31 per cent tariff that Swiss officials had described as "incomprehensible" - is a body blow for the small Alpine nation, which counts the US as the top export market for its watches, jewellery and chocolates.
The White House said on Friday it had made the move because of what it called Switzerland's refusal to make "meaningful concessions" by dropping trade barriers.
"Switzerland, being one of the wealthiest, highest income countries on earth, cannot expect the United States to tolerate a one-sided trade relationship," a White House official said.
Swiss President Karin Keller-Sutter earlier told Reuters the government would keep talking to Washington, but there were only limited concessions it could offer, as US imports already enjoyed 99.3 per cent free market access.
"We have companies that have made very important direct investments (in the US). It's really difficult to give more," she said on the sidelines of a Swiss National Day event in Ruetli.
Switzerland's main export to the US is pharmaceutical products - worth $US35 billion ($A54 billion) last year - though officials said big pharma should not be affected by the higher rate for now.
Swissmem, a group representing the mechanical and electrical engineering industries, said it was "really stunned" by the US move.Â
"It's a massive shock for the export industry and for the whole country," said its deputy director Jean-Philippe Kohl.
"The tariffs are not based on any rational basis and are totally arbitrary ... This tariff will hit Swiss industry very hard, especially as our competitors in the European Union, Britain and Japan have much lower tariffs."
The US is Switzerland's top foreign watch market, accounting for 16.8 per cent of exports, or about 4.4 billion francs ($A8.4 billion), according to the Federation of the Swiss Watch Industry.
Shahzaib Khan, who runs two businesses selling Swiss luxury watches abroad, said the tariffs were "hard to digest".
"This is getting out of hand a little bit... I don't think brands can absorb 39 per cent," Khan told Reuters.
The new rate is set to take effect on August 7, and a Swiss source familiar with the matter said negotiations would continue.
