U.S. trading partners are weighing responses after President Donald Trump’s latest action on tariffs sparked a stock market selloff Monday. The White House sent letters yesterday to about a dozen countries laying out the rates at which imports would be taxed—ranging from 25% to 40%—if no other trade agreements are reached.

President Trump said Japan and South Korea would face tariffs of 25 percent unless they reached an agreement with the United States. Other countries received notice of higher levies.