VIENNA — A once-promising UN attempt to investigate suspicions that Tehran worked on atomic arms is faltering — and with it, hopes that Iran and six world powers can meet their July target date for a comprehensive nuclear deal.
With efforts to draft the text of an agreement starting in Vienna on Wednesday, both sides say that meeting the informal July 20 deadline remains possible. The US administration gives it a 50-50 chance, and Iranian Foreign Minister Mohammad Javad Zarif recently said the talks are progressing at an ''unexpectedly fast pace.''
The United States, Russia, China, Britain, France, and Germany want to reduce Iran's present nuclear weapons-making potential. Tehran has been engaging with them over the past six months in exchange for full sanctions relief, even though it insists it has no interest in such arms.
But the UN's International Atomic Energy Agency is no nearer to closing the books on persistent allegations that Iran worked on nuclear arms in the past. While the IAEA's probe is formally separate from the talks, the United States and its allies insist that Tehran must provide satisfactory explanations as part of any deal.
Back in November, Tehran agreed to go into deeper explanations of its work on detonators that have a variety of uses, including sparking a nuclear explosion.
That has not happened. Three diplomats said Monday that in a recent formal response, Iran continues to insist that there is no nuclear link to the detonators.