Gaps on most major nuclear issues hours before deadline

May 31 midnight is the deadline for the six world powers and Iran to reach a framework deal on Iran’s nuclear program, although a few hours were gained by pushing midnight from Lausanne to Washington standard time. Still outstanding – even after major US concessions – are such issues as centrifuges, the disposition of Iran’s enriched uranium stocks, nuclear research, verification, and the tempo of sanctions relief – all referred to by US Secretary of State John Kerry as “tricky” questions. The diplomats gathered in Lausanne to clinch the deal, as the basis for a final accord by the end of June,  have little hope of reaching an agreed and signed document in the short time remaining. One option for closing the session might be oral announcements by the two sides that leave the controversies open for the next stage of negotiations.