Global markets had previously posted gains on hopes that Trump might be willing to negotiate down the array of country and product-specific trade barriers he is erecting around the world's largest consumer market.
The administration has scheduled talks with South Korea and Japan, two close allies and major trading partners, and Italian Prime Minister Giorgia Meloni is due to visit next week.
But the White House made clear that country-specific tariffs of up to 50 per cent would nevertheless take effect at 12.01am Eastern Time (2pm on Wednesday AEST), as planned.
Those tariffs will be especially steep for China, as Trump has ratcheted up duties on its imports to 104 per cent in response to counter-tariffs Chinese officials announced last week.
Administration officials said they would not prioritise negotiations with China, the world's No. 2 economic power.
Trump's sweeping tariffs have raised fears of recession and upended a global trading order that has been in place for decades.
"Right now, we've received the instruction to prioritise our allies and our trading partners like Japan and Korea and others," White House economic adviser Kevin Hassett said on Fox News.
The White House said Trump instructed his trade team to create "tailor made" deals for the nearly 70 countries that have reached out for talks.
"The president will talk to any country that picks up the phone to call, and I can tell you, the phones have been ringing off the hook," White House spokeswoman Karoline Leavitt told reporters on Tuesday.
Trump's lead trade negotiator, Jamieson Greer, told Congress that his office is trying to work quickly but is not facing a particular deadline.
"The president has been clear, again, that he's not doing exemptions or exceptions in the near term," Greer told a hearing.
China is bracing for a war of attrition, and manufacturers are warning about profits and scrambling to plan new overseas plants.
Citing rising external risks, Citi cut its 2025 China GDP growth forecast to 4.2 per cent from 4.7 per cent.
Chipmaker Micron told customers it will impose a tariff-related surcharge starting on Wednesday while US clothing retailers said they are delaying orders and holding off on hiring.
Running shoes made in Vietnam that retail for $US155 ($A256) will cost $US220 when Trump's 46 per cent tariff on that country takes effect, according to an industry group.
Consumers are stocking up while they can.
"I'm buying double of whatever - beans, canned goods, flour, you name it," Thomas Jennings, 53, said as he pushed a shopping cart through the aisles of a New Jersey Walmart.
Stock markets found a firmer footing on Tuesday after a gut-wrenching few days for investors which prompted some business leaders, including those close to Trump, to urge the president to reverse course.
European shares bounced off 14-month lows after four straight sessions of heavy selling while global oil prices steadied after falling to four-year lows.
Wall Street's main indexes had posted gains earlier in the day but fell after the White House said the tariffs on China would take effect.
The European Commission, meanwhile, is mulling counter-tariffs of 25 per cent on a range of US goods including soybeans, nuts and sausages although other potential items like bourbon whiskey were left off the list.
Officials said they stood ready to negotiate.
