As a candidate in the 2016 presidential election, Trump was an outspoken critic of the deal but had offered conflicting opinions on whether he would try to scrap it, modify it or keep it in place with more strenuous enforcement. Tuesday's determination suggested that while Trump agreed with findings by the U.N.'s nuclear watchdog, the International Atomic Energy Agency, that Iran is keeping to its end of the bargain, he is looking for another way to ratchet up pressure on Tehran.