The White House said on Monday it has noticed that Mexico is "serious" about President Donald Trump's executive order on tariffs, but Canada has "misunderstood" it to be a trade war between the neighboring countries.

What to know as President Donald Trump imposes steep new tariffs on imports from Canada, Mexico and China, prompting retaliation and countermeasures.

Wall Street opened lower after Trump's tariffs on Mexico, Canada and China, sparking fears of trade wars that'll slow economies and ignite inflation.