What Trump ultimately decides to announce on tariffs will be “effective immediately,” White House press secretary Karoline Leavitt said Tuesday. That is logistically dubious, but if that is the case, other nations would have little time to negotiate and could respond by immediately imposing countermeasures such as retaliatory tariffs.

Stocks recoiled on Wednesday, while safe-haven gold held near record highs as a nervous world awaited details of U.S. President Donald Trump's tariff plans and investors fretted about the risks of an intensifying global trade war.

Trump has already restored a 25% tariff on all aluminum and steel imports, tariffs on all Chinese imports, and a 10% tariff on Canadian energy imports. A tariff on all imported vehicles goes into effect Thursday.