The White House announced that it would end a two-month exemption for the EU, Canada and Mexico from the 25% steel and 10% aluminum import tariffs announced in March, once again pointing to national security concerns as a primary motivating factor.

U.S. Commerce Secretary Wilbur Ross said during a call with reporters on Thursday that slow progress on the NAFTA renegotiation is another reason why Canada and Mexico will now be subject to the import tariffs.

The tariffs will go into effect on the trio of countries at midnight.

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