In October 2017 and more explicitly in January 2018, the President linked continued U.S. participation in the Joint Comprehensive Plan of Action (JCPOA) to congressional and allied action to address the deficiencies in the JCPOA that the President identified. On May 8, he announced that the United States would cease implementing the JCPOA, using the mechanism of reimposing suspended U.S. sanctions to implement the U.S. pullout. The May 8 announcement came in advance of a May 12, 2018, date when the existing waiver of a key U.S. sanctions law was to expire. The U.S. withdrawal from the JCPOA will likely have significant implications for U.S. policy in the region. This report bases its analysis primarily on the text of key documents involved in the issue—the JCPOA itself; U.N. Security Council Resolution 2231 of July 20, 2015, which endorsed the JCPOA; and the Iran Nuclear Agreement Review Act (INARA, P.L. 114-17 , of May 22, 2015). The JCPOA does not specifically provide for any party to the agreement to "withdraw." Although European and other diplomats argue that Resolution 2231 makes the agreement binding on all parties under the U.N. Charter, officials in the Obama Administration asserted that the JCPOA is a nonbinding political commitment, and Trump Administration officials continued that assertion. As President Trump noted in his October 2017 and January 2018 statements, he has the authority to cease U.S. implementation of the accord. He has the authority to reimpose all or some of the U.S. sanctions that were revoked or suspended to implement the deal, to reinstate those sanctions imposed by Executive Order, and to redesignate for sanctions entities that were "de-listed" from sanctions to implement the JCPOA. The President's May 8, 2018, announcement that the United States would no longer implement the JCPOA indicated that he would exercise all these options to reimpose all U.S. sanctions that were revoked or suspended to implement the JCPOA. The President apparently does not require the approval of Congress for these courses of action. President Trump's May 8 announcement was widely foreshadowed. On August 1, 2017, then-Secretary of State Tillerson told a press briefing: "The conversation on Iran does not begin and end with the JCPOA, the nuclear agreement, and I think if there's one thing I hope I can help people understand it's that agreement dealt with a very small slice of Iran's threats, and that was their nuclear program." In a speech to the U.N. General Assembly on September 19, 2017, President Trump said We cannot let a murderous regime continue these destabilizing activities while building dangerous missiles, and we cannot abide by an agreement if it provides cover for the eventual construction of a nuclear program. The Iran Deal was one of the worst and most one-sided transactions the United States has ever entered into. Frankly, that deal is an embarrassment to the United States, and I don't think you've heard the last of it, believe me. On October 13, 2017, President Trump announced a new U.S. strategy on Iran, following a six-month policy review. The President raised the possibility that he might terminate U.S. participation in the JCPOA if certain conditions are not met, stating that By its own terms, the Iran Deal was supposed to contribute to "regional and international peace and security." And yet, while the United States adheres to its commitment under the deal, the Iranian regime continues to fuel conflict, terror, and turmoil throughout the Middle East and beyond. Importantly, Iran is not living up to the spirit of the deal.... That is why I am directing my administration to work closely with Congress and our allies to address the deal's many flaws so that the Iranian regime can never again threaten the world with nuclear weapons.... However, in the event we are not able to reach a solution working with Congress and our allies then the agreement will be terminated. It is under continuous review, and our participation can be cancelled by me, as President, at any time. On January 12, 2018, President Trump again threatened to withdraw the United States from the JCPOA unless Congress and the European allies "fix the terrible flaws of the Iran nuclear deal." He identified the "fixes" as (1) a requirement that Iran allow immediate inspections at all sites requested by international inspectors; (2) ensuring that Iran "never even comes close to possessing a nuclear weapon"; (3) the elimination of an expiration date for the JCPOA's nuclear restrictions on Iran; and (4) subjecting Iran's development and testing of missiles to "severe sanctions." The President also called on U.S. allies to "take stronger steps with us to confront Iran's other malign activities," defined as Iran's support for terrorist groups, its development of missiles and their supply to Iran's allies and proxies, Iran's cyber threats, its human rights violations, and its threats to international shipping. After the January 12, 2018, statement, the President replaced Tillerson and National Security Adviser H.R. McMaster with officials who have been critics of the JCPOA. Secretary of State Mike Pompeo, sworn in on April 26, 2018, and National Security Adviser John Bolton, who began his appointment on April 9, 2018, both, prior to assuming their current posts, argued in favor of military action against Iran's nuclear program and for U.S. efforts to change Iran's regime. The May 8 announcement signaled that the Administration seeks to encourage further efforts to address its concerns about the JCPOA and broader Iran issues, possibly in a revised nuclear agreement. According to the May 8 statement As we exit the Iran deal, we will be working with our allies to find a real, comprehensive, and lasting solution to the Iranian nuclear threat. This will include efforts to eliminate the threat of Iran's ballistic missile program, to stop its terrorist activities worldwide, and to block its menacing activity across the Middle East.... Iran's leaders will naturally say that they refuse to negotiate a new deal. They refuse, and that's fine. I'd probably say the same thing if I was in their position. But the fact is, they are going to want to make a new and lasting deal, one that benefits all of Iran and the Iranian people. Global r eacti on to the May 8 announcement tracked closely with the consistent positions taken by countries and leaders on the JCPOA. The decision drew statements of support from Israel, Saudi Arabia, the United Arab Emirates, and Bahrain — all countries that assert that Iran is a major threat to their security. The leaders of France, Germany, and Britain (the three European countries that negotiated the JCPOA alongside the United States)— as well as the EU collectively — issued a joint statement expressing "regret" over the decision. European leaders stated that they remained committed to the JCPOA as "important for our joint security." European diplomats have consistently asserted that the JCPOA is a binding international commitment under Resolution 2231, which endorsed the accord. The European reaction appeared to reflect disappointment in the failure of their efforts to address President Trump's concerns through a supplemental agreement or pledges of joint action. Since President Trump's October 13, 2017, speech, Britain, France, and Germany held numerous meetings with U.S. State Department officials led by senior adviser to the Secretary of State Brian Hook, to discuss potential European steps that could satisfy Mr. Trump's demands. As the May 12 deadline to again waive key sanctions laws loomed, France's President Emmanuel Macron and Germany's Chancellor Angela Merkel each met with President Trump in Washington, DC, during the week of April 23, expressing support for working with the United States on additions to the JCPOA, or other U.S.-European joint action, that would address the expiration of nuclear restrictions, Iran's regional activities, and Iran's ballistic missile programs. President Macron's comments during his visit suggested he might be willing to try to engage Iran (and presumably also Russia and China) in new negotiations regarding these issues. Yet, no firm agreements were announced in the course of the European leadership visits. The European leaders indicated that it would be unwise to risk the collapse of the accord without a clear alternative in place, and both indicated they intended to continue implementing the JCPOA even if President Trump ceases to implement it. According to a senior State Department official briefing reporters after the May 8 presidential announcement The President made clear on January 12 th that he was giving a certain number of months to try to—for—try to get a supplemental agreement with the E3 (Britain, France, and Germany). We didn't get there. We got close. We made a—we had movement, a ton of good progress, which will not be wasted, but we didn't get there.... Iran's President Hassan Rouhani reacted to the May 8 announcement immediately, stating that Iran would work with the remaining parties to the accord to keep it intact. He indicated that Iran would continue to implement its commitments as long as Iran derives the economic benefits of the agreement, an implicit threat that Iran might leave the accord if reimposed U.S. sanctions damage its economy significantly. Paragraph 26 of the JCPOA states that "... Iran has stated that it will treat such a reintroduction or reimposition of the sanctions specified in Annex II, or such an imposition of new nuclear-related sanctions, as grounds to cease performing its commitments under this JCPOA in whole or in part." At the same time, on May 8, Rouhani directed Iran's nuclear program officials to be prepared to restart suspended aspects of Iran's program if the accord collapses entirely. Iranian officials have consistently insisted that they would not renegotiate the JCPOA under any circumstances.