Where will the next US-Iran senior diplomatic meeting take place...?

On June 22, the first round of U.S.-Iran diplomatic talks in Switzerland concluded, with mediators reporting progress toward a roadmap for a final deal and follow-on technical talks expected to continue (see: https://www.aljazeera.com/news/2026/6/22/us-iran-agree-on-roadmap-towards-final-deal-in-switzerland-talks). This market will resolve according to the country in which the next direct or indirect senior-level diplomatic meeting between the United States and Iran begins by December 31, 2026, 11:59 PM ET. A diplomatic meeting occurs when representatives of both listed countries who are acting in an official capacity and are authorized to engage in diplomacy on behalf of their respective governments or governing authorities deliberately meet for the purpose of diplomacy or negotiation. A qualifying meeting need not result in any agreement, joint statement, or further engagement. A diplomatic meeting is senior-level if each listed entity is represented by a head of state, a head of government, or a vice president; a foreign minister; a minister of cabinet rank; the secretary or head of a national security council; the presiding officer of a national legislature; a special envoy; or another individual designated by the head of state or head of government to conduct diplomatic negotiations on their behalf. … (condensed)