Brian Hook, the US policy coordinator for Iran, visited the United Arab Emirates (UAE) this weekend as part of a Middle East tour intended to discuss Washington’s efforts to extend the conventional arms embargo on Tehran, which expires in October.

“Special Representative Hook updated Emirati officials on diplomatic efforts to extend the embargo, and they discussed the risk of an arms race in the region if the embargo is not renewed,” the State Department said in a readout of the envoy’s trip.

Hook met with UAE Foreign Affairs Minister Sheikh Abdullah bin Zayed Al Nahyan, Minister of State for Foreign Affairs Anwar Gargash and Chairman of the Abu Dhabi Executive Affairs Authority Khaldoon Khalifa al-Mubarak.

Why it matters:  The United States has threatened to snap back multilateral sanctions on Iran at the United Nations in the likely event that it fails to convince the Security Council to extend the arms embargo, the first sunset provision to expire as part of the 2015 nuclear deal. However, it remains unclear whether Washington has the authority to instate snapback sanctions given the Donald Trump administration’s 2018 withdrawal from the accord.