capable people around him. >> gary cohn's decision was apparently prompted by the president's plan to impose these tariffs on imported steel and aluminum. nbc news reports tonight that it's unclear when the president will actually sign off on those tariffs. he's now considering an exemption, a carve heat out for countries like mexico and canada. today he continued to press the case for his proposal. >> we have finally given american businesses a level playing field. and you'll see more of this in the coming weeks. we're bringing it back. our jobs have been stolen from us. our businesses have been taken. our factories have been closed. it's all coming back. >> mr. trump's tariff proposal coupled with the impending departure of gary cohn is raising concerns among top congressional republicans, some of whom believe the president