Shares of automakers and megacap tech stocks bore the brunt of a wider equity pullback on Monday after U.S. President Donald Trump ordered sweeping tariffs against Mexico, Canada and China, sparking fears of a global trade war that could hit growth.

Amid warnings of price increases, Canada moved quickly to retaliate, China said it had planned countermeasures and Mexico said it would soon unveil its response.

Canada’s prime minister and Mexico’s president have ordered retaliatory tariffs against Americans, following through with their threats after U.S.