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Another round of nuclear talks between world powers in Iran ended yesterday and negotiations are expected to run through July. The U.S. wants to limit Iran's nuclear program. Iran wants relief from economic sanctions, but there are some mysteries, including rumors and reports about old weapons programs Iran allegedly hid.
And that poses a dilemma. How does it admit to past concealment? Well, it asked the world to trust it under a new deal. NPR's Peter Kenyon reports from the talks in Vienna.
PETER KENYON, BYLINE: The experts call them PMDs, possible military dimensions, to the Iranian nuclear program - at least in the past, as suggested by information given to the International Atomic Energy Agency, under cloudy circumstances. The allegations involve things like conducting experiments on potential nuclear detonators.
And what if any nuclear weapons activity took place at the Parchin military site? Mark Fitzpatrick, with the International Institute for Strategic Studies in London, says admitting to past military applications for its nuclear technology was always going to be extremely difficult for Tehran.
MARK FITZPATRICK: I think it will be very difficult indeed for Iran to admit to past work on weaponization. And most people - most outsiders who look at this see pretty clearly that there was such work.
KENYON: But as hopes for sanctions relief continue to build in Iran, there are signs the government is looking for a solution. Recently, Iran's atomic energy organization said it would produce a comprehensive list of the country's nuclear activities. The question though is when.
In an interview with the Wall Street Journal, deputy foreign minister Madjid Ravanchi said questions about past military issues should be resolved at a later stage. Former IAEA official Tariq Rauf, now with the Stockholm International Peace Research Institute, says the IAEA tends to move at its own pace without regard for the July 20 deadline for the political nuclear talks here in Vienna. But the basic outline of Iran's response is emerging.
TARIQ RAUF: Iran has admitted to carrying out some of its activities, but for civilian applications, such as exploding bridgewire, which is used for mining and oil operations.
KENYON: The technology, which involves a series of rapid explosions, can also be used as nuclear detonator, experts say, which is the cause for concern. A number of analysts say Iran should be able to admit past weapons research, as long as there's no evidence such research is continuing and as long as Tehran agrees to vigorous verification by UN inspectors. But Ali Vaez, author of a recent report by the International Crisis Group on resolving a nuclear stand-off, says there's a chicken and egg problem here.
Iran can't reach a political nuclear deal with the six world powers, known as the P5+1, until it closes its technical file with the IAEA. But Tehran worries that any admission to the IAEA could be used against it in the political talks with world powers. That, says Vaez, is why Iran is trying to put-off the PMD questions until later.
ALI VAEZ: They believe that if they don't improve their relations with the West and resolve the PMD issues after there has been some confidence building in the relationship between Iran and the West, the PMD file will never go away because every once in a while there would be new allegations and this will be a never-ending process.
KENYON: One answer, Vaez believes, is for the P5+1, Iran and the IAEA to meet together and agree on certain high-priority issues to be answered quickly. So far, however, the six world powers have been reluctant to encroach on the IAEA's turf. Whether that changes in the next two months remains to be seen. Peter Kenyon, NPR News, Vienna. Transcript provided by NPR, Copyright NPR.