nuclear weapons. james bayes is in vienna. so how are the negotiating going? >> reporter: it's clearly moving forward, but very slowly. that's because there are still difficulties but also because this is supposed to be the final agreement, so they don't want any misunderstandings. we have had further meetings with the u.s. secretary of state and the iranian foreign minister. we're expecting other foreign ministers to come here in the next few hours. the idea is to give this whole process momentum. perhaps more importantly on thursday, we have a visit from the head of the international at atomic energy agency to tehran to see the president. key in this if there is a deal they have to police the deal. where would their inspectors be allowed to go in would they go to military sites.