"This decision harms American credibility on the world stage, and it is unacceptable," Rep. Eliot L. Engel, ranking Democrat on the House Foreign Affairs Committee, said in a letter to Secretary of State Rex W. Tillerson. "I expect that you will remedy this error at once and explain to me and other lawmakers why this happened in the first place."
"Negotiating additional terms to the nuclear deal requires a coalition of international partners, not unilateral congressional action," Mr. Engel said. "Failing to certify the deal is a risky gamble. It's the first step toward withdrawing from the agreement keeping Iran from building the bomb."