From the Document: "As part of its efforts to maximize pressure on Iran, the Trump Administration is urging a wide variety of international actors to adopt Iran policies similar and complementary to those of the United States. The Administration arguably is attempting to isolate Iran politically and diplomatically by fashioning a multilateral 'coalition of the willing' consisting of U.S. allies and partners in Europe, the Middle East, and Asia. It is implementing its strategy in international issue-focused meetings, special U.S.-organized and long established multilateral forums such as the United Nations, and bilateral discussions. One particular, although not exclusive, goal is to persuade the other JCPOA parties to follow the Trump Administration's May 2018 step of abrogating the multilateral nuclear agreement with Iran (Joint Comprehensive Plan of Action, JCPOA), and reimpose economic sanctions."
CRS In Focus, IF11132
Congressional Research Service: https://crsreports.congress.gov/