Russia and China vetoed a UN Security Council resolution on September 17 that would have extended the mandate of the independent panel monitoring sanctions on Iran. Eleven members supported the measure, while Pakistan and Somalia abstained, ending the panel’s authorization and leaving the council without an independent mechanism to investigate violations and recommend further action. The panel has been absent for the past year because the 15-member council could not agree by consensus on appointing experts. The dispute follows the E3—France, Germany and the United Kingdom—triggering the JCPOA snapback mechanism on August 28, 2025, after accusing Tehran of violating the 2015 nuclear agreement. Sanctions returned on September 27, 2025. Russia and China argue that the nuclear deal removed all UN measures against Iran and have said the Western effort to restore them was illegitimate; they have also maintained that the restrictions expired on October 18, 2025. The International Atomic Energy Agency referred Iran to the Security Council on September 9, 2026, citing non-compliance with its nuclear obligations. US Deputy Ambassador Jennifer Locetta said the missing panel creates a monitoring gap, while Russia’s UN Ambassador Vassily Nebenzia called for political and diplomatic efforts to address the dispute.