The U.S. will initially exempt allies including the European Union, Brazil, South Korea, Argentina and Australia from the steel and aluminum tariffs that the Trump administration will impose Friday, U.S. Trade Representative Robert Lighthizer told the Senate Finance Committee Thursday.

The list is in addition to previously announced temporary exemptions for Canada and Mexico, the United States' partners in the North American Free Trade Agreement.

"The idea that the president has is that based on a certain set of criteria that some countries should get out," Lighthizer told Sen. Ron Wyden, D-Ore. "What he has decided to do is to pause the imposition of the tariffs on those particular countries."

President Trump this month signed a 25 percent tariff on steel imports and 10 percent one aluminum. The actions prompted an outcry from U.S. trade partners, and the administration quickly said it would negotiate to allow some countries to be excluded.

The administration has said it may reimpose the tariffs on Canada and Mexico if they do not make concessions in the NAFTA re-negotiations.