A 2015 multilateral Iran nuclear agreement (Joint Comprehensive Plan of Action, JCPOA), provides for limits on Iran’s nuclear program in exchange for sanctions relief. Annex B of U.N. Security Council Resolution 2231 (July 17, 2015), which endorsed the JCPOA, provided for a ban on the transfer of arms to or from Iran until October 18, 2020. The Trump Administration, supported by many in Congress, sought to extend the ban in order to try to prevent Iran from acquiring new conventional weaponry. On August 14, the U.N. Security Council, including two key potential arms suppliers of Iran—Russia and China—voted down a U.S. draft to extend the arms transfer ban. An overwhelming majority of the Council also has refused to recognize a U.S. assertion that it had standing to implement the provision of Resolution 2231 that enables JCPOA participants to snap back all U.N. sanctions on Iran, including the arms transfer ban. The dispute over the U.S snapback request remains unresolved. Annex B also contains a ban, until October 18, 2023, on supplying equipment with which Iran could develop nuclear-capable ballistic missiles, and calls on Iran not to develop ballistic missiles designed to carry nuclear weapons.

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