Shares of auto giants fell sharply on Monday as U.S. President Donald Trump imposed long-threatened tariffs on goods from Canada, Mexico and China.

WASHINGTON— President Donald Trump on Saturday signed an order to impose stiff tariffs on imports from Mexico, Canada and China, drawing swift retaliation and an undeniable sense of betrayal from the country's North American neighbors as a trade war erupted among the longtime allies.

U.S. President Donald Trump has ordered sweeping tariffs on goods from Mexico, Canada and China, demanding that they curb the flow of illegal immigrants and fentanyl into the United States, kicking off a trade war that could dent global growth and stoke inflation.