Can Iran Withdraw From the NPT? What the Treaty Says and Who Decides

The NPT is the 1968 treaty that limits nuclear weapons to the five states that had tested them before January 1, 1967: the United States, Russia, the United Kingdom, France and China. It opened for signature on July 1, 1968, and entered into force on March 5, 1970. It has 191 parties, more than any other arms control treaty.

It rests on three promises. Countries without the bomb agree never to build or acquire one (Article II) and to accept inspections by the International Atomic Energy Agency (IAEA) on all their nuclear material (Article III). Every member keeps the right to peaceful nuclear energy, including help from others (Article IV). The five nuclear powers commit to negotiate in good faith toward disarmament (Article VI).

Only four countries never joined: India, Pakistan, Israel and South Sudan. India, Pakistan and Israel all built nuclear weapons outside the treaty; Israel has never confirmed its arsenal, which we estimate in how many nuclear weapons Israel has.

Yes. Iran signed the NPT on July 1, 1968, the day it opened, under the Shah, and ratified it on February 2, 1970. The Islamic Republic kept the membership after the 1979 revolution, and its comprehensive safeguards agreement with the IAEA has been in force since May 15, 1974.

Iran’s government still says it is bound by the treaty. Foreign Ministry spokesman Esmaeil Baghaei told reporters in Tehran on November 9, 2026, that Iran remains committed to the NPT, while adding that cooperation with the IAEA cannot return to normal while the US and Israeli attacks on its nuclear sites go on. When parliament first moved against the treaty in March, Baghaei said Iran “has never sought, and does not seek, nuclear weapons.” For two decades Tehran also cited the ruling by the late Supreme Leader Ali Khamenei that nuclear weapons are forbidden.

It sends a written notice, and the exit takes effect three months later. Article X gives each member the right to withdraw if it decides that “extraordinary events, related to the subject matter of this Treaty, have jeopardized the supreme interests of its country.” The notice goes to all other parties and to the UN Security Council and must explain those events.

Nobody has to approve the decision. The treaty gives no other member and no UN body a veto. What the Security Council can do is respond: it may treat a withdrawal as a threat to international peace and impose sanctions under Chapter VII of the UN Charter, as it later did with North Korea.

Withdrawal also has a practical cost for inspections. Iran’s safeguards agreement with the IAEA stays in force only as long as Iran is a party to the NPT, so leaving the treaty would end the legal basis for the inspections it still accepts. In 2026 that means little more than visits to the Bushehr power plant, where Baghaei said IAEA inspectors had worked in the days before November 9. IAEA Director General Rafael Grossi told the Security Council on October 27 that Iran has not given the agency the access or information it needs to verify its nuclear material, including the stockpile we track in how much enriched uranium Iran has.

Only one: North Korea. It first announced its withdrawal on March 12, 1993, then suspended it on June 11, 1993, one day before the 90 days would have run out, after talks with the United States. On January 10, 2003, it announced again that it was leaving and said the exit took effect the next day, arguing that only one day of the 1993 notice was left.

Washington rejected that arithmetic. The State Department said on January 10, 2003, that the 90 days could not be counted as 89 days in 1993 plus one in 2003. The Security Council took no action in 2003. North Korea tested its first nuclear device on October 9, 2006, and the Council imposed sanctions five days later in Resolution 1718. Treaty members still disagree on whether its exit was ever legally complete.

In practice, the Supreme Leader. Iran’s constitution gives him the power to set the country’s general policies, and its Supreme National Security Council answers to him on defense and nuclear matters. The Assembly of Experts, though it appoints and can dismiss the leader, does not make foreign or nuclear policy; its November 12 statement asked officials to act on the “national demand” under Mojtaba Khamenei’s guidance.

Parliament has a bill ready. On March 28, 2026, a month after the US-Israeli strikes that began on February 28, lawmaker Malek Shariati introduced a bill titled “Support for the Nuclear Rights of the Iranian Nation.” It would take Iran out of the NPT, repeal the law that implemented the 2015 nuclear deal and back new nuclear agreements with partner countries. On September 28, First Deputy Speaker Ali Nikzad said lawmakers would examine it with “triple urgency” while weighing its “international implications.” Any bill that passes still needs approval from the Guardian Council, which can veto it. As of November 12 it has not come to a vote.

Iran would be free of the treaty’s ban on building nuclear weapons, and the world would lose its remaining legal right to inspect Iran’s nuclear material. Supporters of an exit in Tehran say staying has bought Iran nothing; Ebrahim Rezaei, spokesman for parliament’s national security committee, wrote on March 27 that NPT membership “has had no benefit for us.” The government’s answer, so far, is that Iran stays in and does not seek a weapon.

The United Nations has already restored its own penalties. UN sanctions on Iran, lifted under the 2015 deal, came back into force on September 28, 2025, after Britain, France and Germany triggered the deal’s snapback mechanism; they include an arms embargo and a ban on nuclear cooperation. A formal notice under Article X would hand the Security Council a fresh case for further action, and it would arrive while Iran’s buried sites, such as the one at Pickaxe Mountain, are already the subject of warnings of new US strikes.

The NPT entered into force on March 5, 1970, and has 191 parties. Article X allows withdrawal with three months’ notice to all parties and the UN Security Council. Iran signed the treaty on July 1, 1968, and ratified it on February 2, 1970. North Korea is the only state to have announced a withdrawal, on January 10, 2003. An Iranian bill to leave the NPT was introduced on March 28, 2026, and has not been put to a vote. Iran’s Assembly of Experts called examining withdrawal “an unavoidable necessity” on November 12, 2026. As of that date, Iran has sent no notice and remains a member.