The Step-by-Step Unravelling of the Iran Nuclear Deal

July 25, 2019

Publication Type: 

  • Articles and Reports

Weapon Program: 

  • Nuclear


Simon Mairson

Tension between Iran and the West has increased over the past year since the United States withdrew from the Joint Comprehensive Plan of Action (JCPOA) and launched a "maximum pressure" campaign aimed at compelling Iran to negotiate a more comprehensive agreement. This tension has thrown the future of the JCPOA into doubt. Key developments since the U.S. withdrawal in May 2018 – including U.S. sanctions, EU mitigation steps, and Iran's response – are explained below.

U.S. Withdraws from the JCPOA amidst Criticism

On May 8, 2018, the United States withdrew from the JCPOA. This agreement, which froze key parts of Iran’s nuclear program, was reached in 2015 by Iran and the P5+1 (China, France, Russia, the United Kingdom, the United States, and Germany). President Donald Trump cited the shortcomings of the deal, including unrestricted missile development and inadequate inspections, as well as the Iranian government’s support of terrorist groups and militias in the region.[1] Effective immediately, U.S. nuclear sanctions on Iran were reinstated. Any new or prospective contract in a proscribed sector was subject to sanction, with sanctions waivers issued during 90 and 180-day “wind-down” periods to allow for existing contracts to be closed.[2] In order to avoid exposure to U.S. secondary sanctions, foreign firms were advised to end their activities during these periods. Iran condemned the decision, asserting that it would not "renegotiate or add on to a deal we have already implemented in good faith,"[3] and called on European countries to protect its oil sales from U.S. sanctions.[4] The remaining parties to the agreement "reconfirmed their commitment to the full and effective implementation of the nuclear deal."[5]

U.S. Sanctions Reimposed in Two Phases

Following the end of the 90-day "wind down" period on August 6, 2018, the United States revoked authorizations related to the import of Iranian carpets and foodstuffs and the sale of commercial aircraft to Iran. Secondary sanctions were reimposed on any foreign party facilitating the purchase or acquisition of U.S. dollar banknotes by the Iranian government, trading with Iran in gold or precious metals, significant transactions involving the Iranian rial, the purchase of Iranian debt, and support of Iran's automotive sector.[6]

In November 2018, following the end of the 180-day "wind down" period, sweeping U.S. secondary sanctions were re-imposed, including on Iran’s port and shipping sector, petroleum-related purchases from Iran, transactions with Iran’s Central Bank and other Iranian financial institutions, the provision of specialized financial messaging services, the provision of insurance, and engagement or investment in Iran’s energy sector. The United States also blacklisted more than 700 individuals and entities, primarily in Iran’s banking, energy, and shipping industries.[7] Nevertheless, the United States initially granted a sanctions waiver to the eight largest buyers of Iranian oil: China, Greece, India, Italy, Japan, South Korea, Taiwan, and Turkey.[8]

European Sanctions Mitigation Efforts

The re-imposition of U.S. secondary sanctions made it difficult for foreign firms with ties to the United States or the U.S. dollar to conduct business with Iran without exposing themselves to these sanctions. The EU took several steps to protect trade with Iran in an effort to provide Iran with some of the economic benefit it expected from the JCPOA. The first step was an updated Blocking Statute that forbid EU compliance with U.S. sanctions and nullified foreign court rulings on the matter.[9] In practice, however, the Blocking Statute was largely a symbolic action; dozens of European firms nevertheless announced plans to leave the Iranian market or withdrew plans to enter it.

The second step came in September 2018, when the EU announced plans to launch a Special Purpose Vehicle (SPV) to facilitate trade with Iran.[10] On January 31, 2019, the Instrument in Support of Trade Exchanges (INSTEX) was created,[11] although it only began processing transactions at the end of June.[12] INSTEX aims to support trade between Europe and Iran, initially in the humanitarian sector, by minimizing international cash flow and instead balancing financial transactions internally. To operationalize the payment mechanism, Iran created a corresponding entity, Special Trade and Finance Instrument (STFI), though its shareholders have been linked to sanctioned entities.[13] It remains to be seen how effective INSTEX can be at mitigating the economic impact of U.S. sanctions against Iran. The initial line of credit for the organization stands at only several million euros, a small fraction of EU-Iran trade prior to the reimposition of U.S. sanctions.[14]

Ramping Up Sanctions

Over the past several months, the United States has imposed additional sanctions aimed specifically at restricting Iran's nuclear complex. In March 2019, the U.S. Department of the Treasury designated 31 individuals and organizations connected to Iran’s Organization of Defensive Innovation and Research (SPND),[15] which has been associated with "possible military dimensions to Iran's nuclear program" according to the International Atomic Energy Agency (IAEA).[16] The United States also revoked several waivers for international nuclear cooperation with Iran specifically allowed by the JCPOA, including the expansion of the Bushehr nuclear power plant and the receipt and storage of Iranian enriched uranium and heavy water.[17] On July 18, the Treasury Department sanctioned a global network of suppliers supporting Iran's uranium enrichment program.[18]

In addition to limiting Iran’s nuclear development, recent U.S. sanctions have targeted the Iranian military and political leadership. In March, the United States designated the Islamic Revolutionary Guard Corps (IRGC) – the elite force which answers directly to Iran’s Supreme Leader – as a foreign terrorist organization.[19] The United States also sanctioned eight senior IRGC commanders as well as Iran’s Supreme Leader Ali Khamenei.[20]

Furthermore, the United States has continued to target Iran's economy – the center of the U.S. maximum pressure campaign. In April, the United States declined to renew waivers that had allowed eight countries to buy Iranian oil, with the aim of stopping all Iranian oil exports.[21] The United States also imposed sanctions on Iran's iron, steel, aluminum, and copper sectors, which represent Iran's largest non-petroleum-related sources of export revenue,[22] and blacklisted Iran’s largest petrochemical company and its subsidiaries.[23] Finally, the United States sanctioned a state-owned Chinese oil trader and the company's chief executive on July 22 for continuing to purchase Iranian oil – the first time such sanctions have been imposed.  

Ongoing Iranian Missile Development and Exports

During the past year, Iran has continued the development and testing of nuclear-capable ballistic missiles. These tests contravene U.N. Security Council resolution 2231, which calls upon Iran "not to undertake any activity related to ballistic missiles designed to be capable of delivering nuclear weapons, including launches."[24] Recent tests include a medium-range ballistic missile launch on December 1,[25] and a pair of space vehicle launches on January 15[26] and February 2,[27] respectively, which involved technologies similar to those used in long-range ballistic missiles.

Iran has transferred some of its missile technology to proxies in the region, including Houthi rebels in Yemen.[28] European parties to the agreement have criticized these actions, which have created additional friction with Iran.

Military Escalation in the Gulf

Recent months have seen a series of tit-for-tat actions between Iran and the West. Since the beginning of May, the United States has sent more than 2,000 troops to Saudi Arabia and deployed additional aircraft in the region, citing the Iranian threat.[29] In May, Iran allegedly attacked an Emirati, a Norwegian, and two Saudi oil tankers in the Gulf of Oman.[30] In June, the United States and the United Kingdom accused Iran of a similar incident involving a Japanese and a Norwegian tanker.[31] [32] In a separate incident one week later, Iran acknowledged shooting down a U.S. surveillance drone that it claimed was flying in Iranian airspace.[33] The United States almost launched a retaliatory strike against Iran but reportedly called it off at the last minute.[34] More recently, British forces detained a tanker in Gibraltar carrying Iranian oil that was allegedly bound for Syria.[35] Iran then seized a British tanker in the Strait of Hormuz.[36] Over 20 percent of the world’s oil exports pass through the strait, which is described by the U.S. Energy Information Administration as "the world's most important chokepoint," setting the stage for continued conflict.[37]

Iran Noncompliance with the JCPOA

On May 8, 2019 – exactly one year after the United States withdrew from the deal – Iran announced a 60-day window for the remaining JCPOA parties to provide sanctions relief before it would stop observing certain terms of the agreement.[38] With Europe unable to fulfill this demand, Iran pushed ahead. In July, Iran announced that it had surpassed the JCPOA’s 300 kg stockpile limit on low-enriched uranium gas[39] and that it had begun enriching uranium beyond the 3.67 percent threshold set by the agreement.[40] Iran is for the moment enriching uranium to 4.5 percent, which is below the level of highly-enriched uranium needed to fuel nuclear weapons. This move appears designed to put pressure on Europe to better mitigate the economic impact of U.S. sanctions. After an additional 60 days, however, the Atomic Energy Organization of Iran (AEOI) said that it would consider increasing the enrichment level to 20 percent.[41] Government officials also affirmed that the AEOI may revert to the previous design of the Arak heavy water reactor, which would provide Iran with weapon quantities of plutonium in its spent fuel.[42] Under the JCPOA, Iran has been working with China and the United Kingdom on a design that would minimize the production of plutonium. Iran exercised restraint in the year following the U.S. withdrawal from the JCPOA, but it appears that this effort is drawing to a close.


[1] “Remarks by President Trump on the Joint Comprehensive Plan of Action,” The White House, May 8, 2018, available at

[2] “Iran Sanctions,” U.S. Department of the Treasury, May 8, 2018, available at

[3] “A Message from Iranian Foreign Minister Javad Zarif,” Iranian Ministry of Foreign Affairs, May 8, 2018, available at

[4] “Iran's top leader sets 7 conditions to remain in nuclear deal -official website,” Reuters, May 23, 2018,

[5] “Statement from the Joint Commission of the Joint Comprehensive Plan of Action,” European Union, July 6, 2018,

[6] “Executive Order 13846: Reimposing Certain Sanctions with Respect to Iran,” The White House, August 6, 2018,

[7] “U.S. Government Fully Re-Imposes Sanctions on the Iranian Regime as Part of U.S. Economic Pressure Campaign,” U.S. Department of the Treasury, November 5, 2018, available at

[8] “U.S. Grants Sanctions Waivers for Iran's Eight Largest Oil Customers,” Reuters, November 7, 2018, available at

[9] “Updated Blocking Statute in Support of Iran Nuclear Deal Enters into Force,” European Union, August 6, 2018,

[10] “Iran Deal: EU and Partners Set Up Mechanism to Protect Legitimate Business with Iran,” European Union, September 25, 2018, available at

[11] “Joint Statement by E3 on the Creation of INSTEX,” European Union, January 31, 2019, available at

[12] “Iran Nuclear Deal: INSTEX Now Operational,” European Union, June 29, available at

[13] Stuart Winer, “US said to mull further Iran sanctions targeting trade with Europe,” The Times of Israel, June 11, 2019,

[14] Henry Foy and Demetri Sevastopulo, “Kremlin throws weight behind EU effort to boost Iran trade,” Financial Times, July 18, 2019,

[15] “U.S. Government Sanctions Organizations and Individuals in Connection with an Iranian Defense Entity Linked to Iran’s Previous Nuclear Weapons Effort,” U.S. Department of the Treasury, March 22, 2019, available at

[16] “Organization of Defensive Innovation and Research,” Iran Watch, September 1, 2014,

[17] “Advancing the Maximum Pressure Campaign by Restricting Iran's Nuclear Activities,” U.S. Department of State, May 3, 2019, available at

[18] “Treasury Sanctions Global Iranian Nuclear Enrichment Network,” U.S. Department of the Treasury, July 18, 2019,

[19] “In the Matter of the Designation of the Islamic Revolutionary Guard Corps (and Other Aliases) as a Foreign Terrorist Organization,” U.S. Department of State, April 15, 2019, available at

[20] “Treasury Targets Senior IRGC Commanders behind Iran’s Destructive and Destabilizing Activities,” U.S. Department of the Treasury, June 24, 2019, available at

[21] “President Donald J. Trump Is Working to Bring Iran’s Oil Exports to Zero,” The White House, April 22, 2019, available at

[22] “Statement from President Donald J. Trump Regarding Imposing Sanctions with Respect to the Iron, Steel, Aluminum, and Copper Sectors of Iran,” The White House, May 8, 2019, available at

[23] “Designations Targeting Iran’s Largest Petrochemical Company for Support to Iran’s Islamic Revolutionary Guard Corps (IRGC),” The White House, June 7, 2019, available at

[24] “Resolution 2231 (2015),” UN Security Council, July 20, 2015, available at

[25] “Iran Test Launches Ballistic Missile Violating UN Security Council Ban,” U.S. Department of State, December 1, 2018, available at

[26] “Iran's Firing of Space Launch Vehicle Defies International Community,” U.S. Department of State, January 15, 2019, available at

[27] “Attempted Space Launch by the Iranian Regime,” U.S. Department of State, February 7, 2019, available at

[28] Michelle Nichols, “Two missile launchers found in Yemen appear to be from Iran: U.N.,” Reuters, December 11, 2018,

[29] Thomas Gibbons-Neff, “U.S. to Send About 500 More Troops to Saudi Arabia,” The New York Times, July 18, 2019,

[30] “U.S. Says Iran Likely Behind Ship Attacks,” The Wall Street Journal, May 13, 2019, available at

[31] David D. Kirkpatrick, Richard Pérez-Peña, and Stanley Reed, “Tankers Are Attacked in Mideast, and U.S. Says Video Shows Iran Was Involved,” The New York Times, June 13, 2019,

[32] “Gulf of Oman Attacks: UK Statement,” U.K. Foreign and Commonwealth Office, June 14, 2019, available at

[33] “U.S. Central Command Statement: Iranians Shoot down U.S. Drone,” U.S. Department of Defense, June 20, 2019, available at

[34] Michael D. Shear, Helene Cooper, and Eric Schmitt, “Trump Says He Was ‘Cocked and Loaded’ to Strike Iran, but Pulled Back,” The New York Times, June 21, 2019,

[35] “Gibraltar Seizes Syria-Bound Tanker Thought to Be Carrying Iranian Oil,” The New York Times, July 4, 2019, available at

[36] “Iranian actions in the Strait of Hormuz: Foreign Secretary's statement,” U.K. Foreign and Commonwealth Office, July 20, 2019,

[37] “World Oil Transit Chokepoints,” U.S. Energy Information Administration, July 25, 2017,

[38] “Iran Gives Parties to JCPOA 60-Day Moratorium to Remedy Breaches,” Islamic Republic News Agency, May 8, 2019, available at

[39] “Zarif: Iran Goes beyond 300kg Enriched Uranium,” Islamic Republic News Agency, July 1, 2019, available at

[40] “2nd Phase of Reduced Commitment to JCPOA Takes Effect: AEOI Spox,” Islamic Republic News Agency, July 8, 2019, available at

[41] Ibid.

[42] “Iran May Restore Arak's Old Reactor if JCPOA Partners’ Measures Slows Down,” Islamic Republic News Agency, July 22, 2019, available at