US‑Iran 'two tracks' debate

The argument over U.S.-Iran diplomacy has narrowed to one question: can nuclear limits be negotiated separately from the wider wars and militias around Iran. (state.gov) The nuclear track is the 2015 Joint Comprehensive Plan of Action, or JCPOA, which traded limits on Iran’s nuclear program for relief from nuclear-related sanctions. The deal was endorsed by United Nations Security Council Resolution 2231 on July 20, 2015. (state.gov) (main.un.org) The regional track covers Iran’s role in conflicts and armed groups across the Middle East, a category the U.S. still treats separately from the nuclear file in its sanctions architecture. The State Department’s current Iran sanctions page says U.S. restrictions rest on multiple legal authorities, not only nuclear ones. (state.gov) That split got harder to sustain after the JCPOA’s sanctions framework unraveled in 2025. On September 19, 2025, the Security Council rejected a bid to continue sanctions relief for Iran, and the European Union reimposed suspended nuclear-proliferation measures on September 29, 2025 after the E3 triggered the deal’s snapback mechanism. (news.un.org) (consilium.europa.eu) The United States then moved from preserving the old deal to enforcing renewed U.N. restrictions. On January 27, 2026, the State Department said the U.S. and 40 countries met in Prague to advance implementation of the reimposed Security Council resolutions on Iran. (state.gov) Iran’s nuclear program also kept moving while diplomacy stalled. The International Atomic Energy Agency reported on May 31, 2025 that Iran was producing uranium enriched up to 60% U-235 at Fordow at a rate of more than 34 kilograms per month, and it has said Iran stopped implementing its JCPOA commitments, including the Additional Protocol, on February 23, 2021. (iaea.org 1) (iaea.org 2) That is why the “two tracks” debate has become more than a negotiating slogan. If sanctions relief now touches U.N., European, and U.S. measures adopted under different authorities, any return to a nuclear bargain runs into the region-wide disputes that Washington says should stay separate. (consilium.europa.eu) (state.gov) The legal language circulating online comes from treaty law, not the nuclear file itself. The Vienna Convention on the Law of Treaties says treaties are binding and must be performed in good faith, a rule lawyers summarize as pacta sunt servanda. (legal.un.org) That principle is often invoked to argue that outside powers should match pressure with compliance to past commitments. But the current Iran file is no longer just the 2015 text: by late 2025, the U.N. and EU sanctions relief built into Resolution 2231 had already been reversed, and U.S. sanctions remained layered across nuclear, missile, petroleum, and regional authorities. (main.un.org) (consilium.europa.eu) (state.gov) The next test comes in a crowded diplomatic calendar, not a single summit. The 2026 Nuclear Non-Proliferation Treaty Review Conference opens in New York on April 27, 2026, six days from now, with Iran’s safeguards record, sanctions enforcement, and the question of whether any track can still be isolated all headed back into the same room. (state.gov)