VIENNA (AP) -- Iranian and U.N. officials held a "constructive" meeting on resuming a probe of allegations that Tehran has worked on atomic arms, officials said Friday after talks seen as an encouraging test of pledges by Iran's new president to reduce nuclear tensions.
The upbeat assessment and an agreement to meet again Oct. 28 was a departure from the deadlock left by previous meetings over nearly two years.
At issue are suspicions outlined in reports from the U.N.'s International Atomic Energy Agency that Iran worked secretly on trying to develop nuclear weapons -- something Tehran denies. As part of its probe, the agency is trying to gain access to a sector at Parchin, a sprawling military establishment southeast of Tehran.
Iran says it isn't interested in atomic arms, but the agency suspects the site may have been used to test conventional explosive triggers meant to set off a nuclear blast. Under former President Mahmoud Ahmadinejad, Iran blamed the IAEA for the standoff, saying it is caused by the agency's refusal to agree on strict parameters that would govern its probe under a so-called "structured approach."
The agency in turn said such an agreement would tie its hands by putting limits on what it could look for and whom it could question. It bases its suspicions of nuclear-weapons research and development by Iran on its own research and intelligence from the U.S., Israel and other Iran critics.
Neither side on Friday went into detail on what went into their positive assessment of the meeting. But senior IAEA official Herman Nackaerts said it was "very constructive," while Iranian envoy Reza Najafi spoke of a "constructive discussion." Nackaerts said the next round Oct. 28 would be "substantive."
A diplomat familiar with the talks said that with the two sides deadlocked over the "structured approach" they discussed possibly abandoning efforts to agree on the document and starting anew. He also said that Najafi was significantly more straightforward than his predecessor at what was his first meeting Friday on the issue.
The diplomat demanded anonymity because he wasn't allowed to discuss the confidential talks.
The meeting was closely watched by the U.S. and its allies as a test of whether Rouhani, Ahmadinejad's successor, was ready to deliver on promises that he sought to end Iran's nuclear standoff with the international community.
Its positive outcome was the latest in a series of encouraging developments along that line.
On Thursday, the U.S. and its five negotiating partners emerged from a separate meeting with Iran declaring that a "window of opportunity has opened" to peacefully settle their nuclear standoff.
Both sides agreed to a new round of talks Oct. 15-16 in Geneva, where Tehran will seek relief from crippling sanctions and the six nations will press Iran to scale back an atomic program that could be re-engineered from peaceful purposes to producing weapons.
In contrast to Ahmadinejad, Rouhani has come across as a more moderate face of the hard-line clerical regime in Tehran and his pronouncements at this week's U.N. General Assembly have raised guarded hopes that progress might be possible. But they have also served as a reminder that the path to that progress won't be quick or easy.
He has steadfastly maintained that any nuclear agreement must recognize Iran's right under international treaties to continue enriching uranium. Iran now is enriching below the level used as the core of nuclear missiles, but its critics fear it is at the threshold where it would be able to quickly revamp its program to produce weapons-grade uranium.
In comments to reporters at the United Nations on Friday, Rouhani said that President Barack Obama struck a new tone in his U.N. speech this week that left him optimistic about easing tensions between the two countries.
Rouhani also said the recent elections that propelled him to the Iranian presidency created a "new environment" that could pave the way for better relations with the West.
The IAEA-Iran talks held Friday are separate from negotiations between Tehran and the U.S., Russia, China, Britain, France and Germany. But with both sides at the Vienna talks speaking of progress, expectations appeared to be building for headway at a Nov. 15-16 meeting between Iran and the six world powers in Geneva.
The deadlock over Parchin and related issues remained despite 10 rounds previous to Friday's meeting. IAEA chief Yukiya Amano told reporters earlier this year he was concerned about satellite images showing asphalt work, soil removal, and "possible dismantling of infrastructures" at the site.
Iran says such activities are part of regular construction that has nothing to do with alleged attempts to cleanse the area of evidence. But Amano said that because of such activities, "it may no longer be possible to find anything even if we have access to the site."
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