Iran formally declared on Saturday, 18 October, that it is no longer bound by the nuclear restrictions of the 2015 Joint Comprehensive Plan of Action (JCPOA) - marking the end of a decade-long framework that once tightly limited Tehran's nuclear activities in exchange for sanctions relief.

The deal's expiration also concludes UN Security Council Resolution 2231, which had provided the legal basis for oversight by the International Atomic Energy Agency (IAEA).

Iran's foreign ministry said that "all provisions and restrictions related to the nuclear program are now considered void," but insisted the country "reaffirms its firm commitment to diplomatic engagement."

Why it matters:

The end of UN oversight marks a turning point in global nuclear diplomacy. Iran is now free from the last remaining formal constraints on its uranium enrichment, while Western powers - who accuse Tehran of edging closer to weapons-grade enrichment - have lost their principal inspection framework.

The development underscores a growing divide between Western and Eastern powers over Iran's nuclear future.

The big picture:

Snapback sanctions and diplomatic fallout:

In August, Britain, France, and Germany (the E3) triggered the "snapback" mechanism, seeking to reimpose broad UN sanctions, arguing Iran had breached the deal.

That move drew sharp rebukes from Iran, Russia, and China, who called it "legally and procedurally flawed."

In a joint letter to the UN, the three countries said the European powers had "ceased performing their own commitments" and thus lacked standing to invoke the mechanism.

The letter declared that the end of Resolution 2231 "marks the end of the Security Council's consideration of the Iranian nuclear issue" and "contributes to strengthening the authority of the Council and the credibility of multilateral diplomacy."

What they're saying:

What's next:
With the JCPOA and its UN framework now expired, Iran faces little formal restraint - but also rising diplomatic isolation from the West.

At the same time, Russia and China's open support signals a deepening alignment among the three nations against Western sanctions. The next phase of the nuclear standoff may be shaped less by multilateral agreements and more by shifting geopolitical alliances.

The end of UN oversight doesn't just mark the sunset of the Iran nuclear deal - it marks a new global divide over who gets to enforce nuclear norms.

Iran / Iran nuclear deal / Russia / China / United Nations (UN)