1949: The Israel Defense Forces find sources of uranium in the Negev desert.

1950s: Iran’s nuclear program begins with U.S. assistance as part of the “Atoms for Peace” program, which began under

U.S. President Dwight D. Eisenhower’s administration. This collaboration would come to a halt with the toppling of the Shah of Iran in the 1979 Iranian Revolution.

1953: Iran launches a civilian nuclear program initiative with the aim of reaching nuclear cooperation agreements with other nuclear-capable states.

1955: The United States agrees to sell Israel a small nuclear research reactor.

1957: Israel begins work on the Negev Nuclear Research Facility, a large reactor in the desert near Dimona, which would become the foundation for Israel’s nuclear program in the following years. France begins to build a reactor for Israel and helps with the construction of the Negev facility.

1959: The Tehran Nuclear Research Center (TNRC) is established at Tehran University.

1960s: Steps to establish a nuclear weapons-free zone in the Middle East begin. The Committee for the Denuclearization of the Middle East (a group of Israeli intellectuals) proposes the idea first in 1962, publicly stating that the development of nuclear weapons “constitute[s] a danger to Israel and to peace in the Middle East,” urging the United Nations to intervene “to prevent military nuclear production”.

May 1961: The U.S. Atomic Energy Commission (AEC) sends inspectors to Dimona. The results affirm that Dimona only had a research reactor and was not capable of producing weapons-grade plutonium. This is reaffirmed by a second inspection in September 1962.

1963: Israel agrees to buy 100 tons of uranium ore from Argentina in a secret agreement in response to rising tensions between the United States and Israel.

1967: Tehran Research Reactor (TRR) begins operation at TNRC; 1967 is the most commonly cited date for when Israel first crossed the nuclear threshold—although estimates range from 1965–1968; during the 1967 Six-Day War, it is alleged Israel built a nuclear weapon to be used as a last resort.

1968: The Treaty on the Non-Proliferation of Nuclear Weapons (NPT) is opened for signature. The treaty recognizes five states as “nuclear weapons states”: the United States, the Soviet Union, the United Kingdom, France, and China. With the exception of Israel, all states in the Middle East have signed and ratified the treaty as of today.

1973: During the October 1973 war, it is speculated that Israel once again considered a nuclear test.

1974: The Atomic Energy Organization of Iran (AEOI) is established and decides to set up the Isfahan Nuclear Technology Center to develop nuclear technology; Iran signs a $1.2 billion deal with the France-based Eurodif consortium to enrich uranium on power facilities; Iran signs agreements with West German and French companies to build reactors in Bushehr and Bandar Abbas; Iran concludes NPT Safeguards Agreement, enabling the International Atomic Energy Agency (IAEA) to independently verify the accuracy of Iran’s declarations about its nuclear material and activities.

December 9, 1974: Egypt and Iran’s proposed Resolution 3236 to the United Nations General Assembly for the establishment of a Middle East Nuclear Weapons Free Zone (MENWFZ) is approved.

1975: U.S. Secretary of State Henry Kissinger signs U.S.–Iran Nuclear Cooperation memorandum endorsing a $6.4 billion deal for six to eight nuclear reactors.

1978: The United States finally agrees to let Iran reprocess U.S.-supplied nuclear fuel in exchange for implementing additional safeguards.

1978–1991: Project 922, Iraq’s project to produce chemical and biological weapons, is initiated. Much of the produced chemical weapons agents are used against Iran during the Iran–Iraq War (1980– 1988), and on the Kurdish people during the Persian Gulf War of 1991.

1979: The 1978 agreement between Iran and the United States is terminated as the Islamic Revolution sees the overthrow of the Shah and Ayatollah Khomeini’s ascension, and the United States stops supplying enriched uranium to Tehran. All nuclear cooperation between the United States and Iran is eventually suspended after the U.S. Embassy hostage crisis.

1980: Israel joins the international consensus regarding the Middle East Nuclear Weapons Free Zone (MENWFZ), which allows the General Assembly to pass a resolution with the goal of establishing the zone.

1980-1991: Iran secretly restarts and significantly expands its nuclear program.

1981: The Israeli Air Force bombs and damages the Iraqi Osirak reactor, claiming it as an act of self-defense; the bombing of Osirak would lead to the “Begin Doctrine,” the Israeli policy of counter-proliferation whereby it would preempt the emergence of weapons of mass destruction by military means. Israeli Prime Minister Menachem Begin called the decision “a precedent for every future government in Israel”.

1981-1984: Saddam Hussein’s regime intensifies chemical weapons development. In January 1981, testing of chemical weapons begins, and they are first used on the battlefield in a limited form against Iranian forces between August 1983 and December 1983. By the end of the Iran– Iraq War in 1988, chemical weapons are used extensively by both sides.

1983: Iran asks the IAEA to provide technical assistance with the production of uranium hexafluoride (UF6), a gas compound used for uranium enrichment.

1984: Iran establishes its nuclear research facility in Isfahan.

1986: Mordechai Vanunu, former nuclear technician, now widely renowned Israeli whistleblower, reveals the details of Israel’s nuclear program to the British press. Vanunu had worked at Dimona for eight years and had secretly taken photos of the nuclear complex.

1987: U.S. Executive Order 12613 prohibits the import of Iranian products and oil into the United States; Iran signs a $5.5 million deal with Argentina to supply a new TRR core.

March 16, 1988: During the Al-Anfal Campaign against the Kurdish population, Saddam Hussein wages chemical warfare in what is now called the Halabja chemical attack, a massacre of around 3,200–5,000 Kurds in Halabja during the Iraq–Iran War.

1989: The IAEA General Conference requests that the director-general issue a study titled, “A Technical Study on Different Modalities of Application of Safeguards in the Middle East,” analyzing the status of nuclear activities and safeguards in the region. Following the preparation of this study, the director-general would go to a number of states in the region for consultation regarding the agency’s safeguards.

1990s: Discussions on regional arms control take place under the Arms Control and Regional Security (ACRS) working group as part of the Middle East peace process. ACRS consisted of thirteen Arab states, Israel, a Palestinian delegation, and extra-regional entities. The process eventually collapsed in 1995 with the talks being put on hold indefinitely due to fundamental differences between Egypt and Israel over how to address the issue of nuclear weapons in the Middle East.

1990: Egyptian President Hosni Mubarak launches an initiative to establish in the Middle East a zone free from all weapons of mass destruction without exception.

1990-1991 Gulf War: Iraq fires scud missiles multiple times at Israel and Saudi Arabia. Israel threatens retaliation against Iraq in July. Israeli Science Minister Yuval Ne’eman states, “In my opinion, we have an excellent response, and that is to threaten Hussein with the same merchandise.” Eliyahu Ben Elissar, chair of the Knesset Defense and Foreign Affairs Committee, says “Iraq, after the first use of a missile, won’t be the same Iraq anymore.” This is reiterated by Israeli air force commander Avihu Ben-Nun, who says in a 1991 interview that Saddam would be committing suicide if he fired a missile at Israel.

1991: The U.N. Secretary General releases a report titled “Study on Effective and Verifiable Measures which Would Facilitate the Establishment of a NWFZ in the Middle East,” focusing on confidence-building measures. From 1991 to 1995, the ACSR talks take place between Arab countries and Israel, with Turkey as the designated facilitator. These talks would include a total of forty-two meetings over four years.

1991-1998: The IAEA and the United Nations Special Commission (UNSCOM) on Iraq dismantles all known WMDs in Iraq.

April 3, 1991: UNSC Resolution 687 is passed, which stipulated that Iraq must be rid of all biological, chemical, and nuclear weapons, as well as the facilities that produced them, and endorsed the goal of establishing a zone free of all WMDs.

1995: Delegates to the Review and Extension Conference of the NPT agree to extend the treaty indefinitely. Among the decisions adopted at the conference was a resolution calling for “the establishment of an effectively verifiable Middle East zone free of weapons of mass destruction, nuclear, chemical and biological, and their delivery systems”. Repeated attempts to hold a conference to agree on a negotiating process for the establishment of the zone have failed.

November 2002: The IAEA adopts a resolution for Iran’s decision to sign the Additional Protocol, a protocol to a safeguards agreement that provides additional tools for verification and to suspend enrichment.

February 2003: Iran acknowledges the existence of secret nuclear facilities at Natanz and other locations, and announces that it had extracted uranium from a newly discovered mine in Savand; Iran accepts modifications in NPT Subsidiary Arrangements, requiring the country to notify the IAEA of intentions to set up nuclear facilities; it is not ratified by parliament.

May 31, 2003: The Proliferation Security Initiative (PSI) is launched by President George W. Bush, aiming to counter WMD proliferation. The PSI is a global effort to stop the trafficking of WMDs, launched by Bush in 2003 in Poland and has now grown to include 105 nations.

June 6, 2003: The IAEA issues a report stating that Iran has secret nuclear activities they failed to report.

October 2003: Iran enters negotiations with the EU-3 (France, Germany, and the United Kingdom) to cooperate with the IAEA, and signs the Additional Protocol until February 2006, when Iran would end its obligations under the Additional Protocol and continue enrichment at Natanz.

November 2003: Iran announces temporary suspension of its uranium enrichment program.

December 2003: Iran signs the Additional Protocol; it is not ratified by parliament. Muammar Gaddafi announces Libya has made the decision to eliminate Libya’s WMD program.

2004: Iran acknowledges covert program to acquire nuclear technology; Iran announces plan to build a heavy-water nuclear reactor; Iran reveals production of hexafluoride gas used to enrich uranium, ignoring the IAEA’s demand for suspension of all enrichment activities; Iran and EU3 sign the Paris Agreement, under which the EU3 and Iran would negotiate on guarantees that its nuclear program is meant for peaceful purposes and on commitments on nuclear, technology, and economic cooperation.

February 2005: Iran and Russia sign an agreement for Russia to supply the Bushehr nuclear facility with fuel and Iran to return the fuel rods to ensure enriched uranium is not used for the production of nuclear weapons.

August 1, 2005: Iran notifies the IAEA that it would resume uranium conversion activities at Isfahan. Iran’s breach leads to the IAEA finding Iran noncompliant.

August–September 2005: Iran rejects the EU3’s Long Term Agreement. The IAEA finds Iran in noncompliance with its safeguards obligations.

January 2006: Iran announces that it has achieved the capacity to extract uranium from ore; Iran breaks IAEA seals at the Natanz facility.

February 2006: The IAEA refers Iran to the UNSC for noncompliance of the Safeguards Agreement after reporting inconclusive findings about Iran’s nuclear program.

March 15, 2006: The UNSC calls on Iran to cooperate with the IAEA in a released presidential statement.

July 2006: The UNSC passes Resolution 1969, which demands Iran’s suspension of enrichment, banning the international transfer of any activities related to nuclear and missile technologies, and freezing foreign assets of individuals and organizations related to Iran’s nuclear program.

September 6, 2007: An Israeli airstrike destroys Syria’s nuclear reactor located in the Der Al-Hadjar region, killing ten North Korean nuclear scientists. Although Syria has denied Israeli intelligence officials’ claims that it was a plutonium production reactor, the IAEA confirmed that it indeed was after three years of investigation in May 2011.

November 2007: The IAEA report states that Iran has “provided sufficient access to individuals and responded in a timely manner to questions” regarding its nuclear program; IAEA Director-General Mohamed ElBaradei calls on Iran to suspend uranium enrichment activities and fully implement the Additional Protocol; Iran acknowledges that it acquired nuclear technology, including P-2 centrifuge blueprints, from the Al-Qaeda Khan network over the past two decades;

U.S. National Intelligence Estimate states, “We judge with high confidence that in fall 2003, Tehran halted its nuclear weapons program.”

September 21, 2009: Iran announces it is building a second pilot enrichment facility, the Fordow Fuel Enrichment Plant (FFEP).

October 1, 2009 and October 19, 2009: Iran resumes talks with P5+1, the UNSC’s five permanent members— China, France, Russia, the UK and the United States, plus Germany, agreeing to IAEA inspections at FFEP.

November 2009: The IAEA condemns Iran for developing the secret uranium enrichment site near Qom; Iran announces plans to establish ten additional enrichment sites.

2010: NPT Review Conference discusses disarmament in the Middle East, nuclear non-proliferation and implementing the MENWFZ. For the first time, parties agree on five steps to implement the 1995 NPT Review Conference Middle East Resolution, including convening a regional conference in 2012 and appointing a facilitator for a conference on establishing a WMD-free zone in the Middle East, both proposals largely based on prior Egyptian proposals.

February 7, 2010: Former Iranian President Mahmoud Ahmadinejad tells the IAEA that Iran produced 20 percent enriched uranium and has the ability to continue to do so, escalating tensions with the international community.

March 2011–present: The Syrian Civil War witnesses use of chemical weapons, including the Ghouta attack of August 2013 in Damascus, the Khan Al-Assal attack of March 2013 in Aleppo, the Khan Shaykhun chemical attack of April 2017, and the Douma chemical attack of April 2018.

June 9, 2011: Syria is found in noncompliance with its obligations of the IAEA safeguards obligations under the NPT.

2012: The NPT conference on operationalizing a WMD-free zone in the Middle East is postponed due to lack of consensus.

November 23, 2012: The United States announces it is postponing the Helsinki conference, claiming it is due to the situations in the Middle East and a lack of communication between states in the region.

April 29, 2013: Egypt’s delegation walks out of the 2013 PrepCom NPT meeting in response to the “unacceptable and continuous failure to implement the 1995 Middle East Resolution,” Egyptian Ambassador Hisham Badr announces regarding his delegation’s dramatic walkout.

June 2013: Hassan Rouhani, who had served as Iran’s chief nuclear negotiator from 2003 to 2005, wins the Iranian presidential elections, stating his priority will be “lifting of the oppressive sanctions,” which would lead to secret bilateral talks in March 2013 between the P5+1 and the United States in Oman.

September 14, 2013: Syrian chemical weapons disarmament process begins.

September 27, 2013: The Executive Council of the Organisation for the Prohibition of Chemical Weapons (OPCW) adopts a decision, “Destruction of Syrian Chemical Weapons,” detailing the steps for Syria’s chemical weapons disarmament process. The United Nations Security Council Resolution 2118 requires Syria to eliminate its chemical weapons stockpiles and to allow inspections by the UN and the OPCW.

November 24, 2013: The result of the October 15–16, 2013 talks in Geneva is an agreement on a Joint Plan of Action (JPOA), which outlines the steps for the next six months and goals for the longer-term. The Framework for Cooperation (FFC) is also agreed upon by both parties.

January 2014: The JPOA goes into effect, and Iran converts most of its low enriched uranium (LEU) containing nearly 20 percent uranium-235 for other uses, diluting the rest of the stored LEU so it complies with the terms of the agreement, and provides the IAEA with information regarding its nuclear program.

July 14, 2015: Iran and the P5+1 conclude the Joint Comprehensive Plan of Action (JCPOA) to curtail Iran’s sensitive nuclear fuel cycle activities.

July 20, 2015: The NPT and UNSC adopt Resolution 2231, outlining the legal framework for Iran’s nuclear program. UNSC Resolution 2231 requests the IAEA director-general “to undertake the necessary verification and monitoring of Iran’s nuclear-related commitments for the full duration of those commitments under the JCPOA”.

January 4, 2016: OPCW states Syria’s disarmament of chemical weapons is completed, although many still suspect there are undisclosed sites, with the Douma and Khan Shaykhun attacks further supporting this.

November 19, 2016: Egypt and Russia sign an agreement for Russia to build a nuclear power plant in Dabaa, Egypt.

October 13, 2017: President Donald Trump announces the United States would no longer certify Iran’s compliance with JCPOA.

November 2017: Saudi Arabia announces plans for the construction of two reactors to be launched in 2020.

April 30, 2018: Israeli Prime Minister Benjamin Netanyahu reveals over 100,000 documents Israeli intelligence gathered on Iran’s nuclear weapons program, stating Iran’s compliance with JCPOA had been a pretense. Iranian Defense Minister Brig. Gen. Amir Hatami responds by saying this was a “baseless and unfounded … propaganda show”.

May 8, 2018: President Trump announces the United States will reimpose sanctions on Iran, a decision that elicits an international backlash, and leads to the

U.S. withdrawal from JCPOA. Trump says in a speech that “the heart of the Iran deal was a giant fiction: that a murderous regime desired only a peaceful nuclear energy program”.

August–November 2018: Trump’s administration reimposes first round of economic sanctions on Iran; a new round of sanctions targeting Iran’s economy is imposed by Trump’s administration, this time specifically targeting the oil and banking sectors.

May 2, 2019: The United States ends waivers that allowed eight countries (China, Greece, India, Italy, Japan, South Korea, Taiwan, and Turkey) to buy Iranian crude oil.

May 8, 2019: Trump imposes more sanctions on Iran, targeting the steel, aluminum, and copper industries.

May 12, 2019: Four ships in waters off the United Arab Emirates are attacked— the United States blames Iran but Iran denies the charge.

May 24, 2019: Trump sends 1,500 troops to the Middle East in order to counter Iran.

June 13, 2019: Two tankers are attacked in the Strait of Hormuz. The United States blames Iran but Iran denies the charge.

June 20, 2019: Iran shoots down a U.S. military drone which it claims was flying in its airspace. The United States denies it was over Iranian territory.

June 24, 2019: Trump imposes more sanctions on Iranian leaders, including Supreme Leader Ayatollah Ali Khamenei.

July 1, 2019: Iran’s Foreign Minister Mohammad Javad Zarif announces that unless Europe takes measures to circumvent U.S.-imposed sanctions on Iran by July 7, Iran will continue to breach the limits of the amount of low-enriched uranium accumulated, and increase its uranium enrichment level beyond 3.67 percent.

July 7, 2019: Iran threatens to boost uranium enrichment above the designated threshold determined in the 2015 nuclear deal and says it will refuse to abide by its commitments to the deal.

July 19, 2019: Iran seizes British oil tankers Stena Impero and Mesdar, leading to heightened tensions between the West and Iran.

July 24, 2019: Syrian state television says reports showed Israeli attack in southern Syria, Tel Haraa, which is allegedly where Iranian-backed militias are based.

July 28, 2019: Britain, France, Germany, Russia, and China meet with Iran in Vienna to discuss JCPOA and save the 2015 nuclear accord.

September 4, 2019: Iranian President Rouhani states Iran will lift “all limitations” imposed on its development of centrifuges used for uranium enrichment, and gives Europe two months to fulfil their commitments to shield the Iranian economy from the effects of U.S. sanctions to save the nuclear deal.

September 7, 2019: Iran announces it has begun to use new measures to enrich uranium by activating 20 IR-4 and 20 IR-6 centrifuges, breaching the limit Iran is allowed to stockpile.