"As part of a shift to assertively counter Iran's regional activities and strategic weapons programs, the Trump Administration has designated for sanctions additional missile and IRGC-Qods Force entities. The Administration asserts its steps do not conflict with U.S. commitments under the JCPOA [Joint Comprehensive Plan of Action] and the Administration has continued to implement the agreement, including renewing waivers of sanctions laws suspended in accordance with the JCPOA. However, the Administration has announced an Iran policy review and, were the Administration to decide to end U.S. participation in the JCPOA, it could revoke waivers, decline to renew waivers, or sign new sanctions legislation or issue Executive Orders that breach the JCPOA. Some Iran sanctions legislation has advanced in the 115th Congress, such as S. 722. The reimposition of many or all U.S. sanctions would undoubtedly harm Iran's economy. "
CRS Report for Congress, RS20871
Federation of American Scientists: http://www.fas.org/sgp/crs/index.html