By Justyna Pawlak
BRUSSELS (Reuters) - Experts from Iran and six world powers will meet in Vienna on October 30-31 to prepare the next round of high-level talks on the contested Iranian nuclear program with hopes of a breakthrough rising thanks to a diplomatic opening from Tehran.
Western diplomats say the meeting, scheduled to take place a week before the next round of negotiations in Geneva in November, could be instrumental in defining the contours of any preliminary agreement on Iran's uranium enrichment campaign.
After years of diplomatic paralysis and increasingly confrontational rhetoric, the June election of Iranian President Hassan Rouhani, a relative moderate, has opened windows to a deal that would head off the risk of a new Middle East war.
At talks with the six world powers - the United States, Russia, China, France, Britain and Germany - last week, Iranian negotiators expressed readiness to address Western concerns over the program but left many details unanswered about specific concessions they may be willing to make, diplomats said.
In meetings over the last two years, the six powers asked Iran to stop enriching uranium to 20 percent fissile purity, a process that takes a major technological step en route to making bomb fuel, and to ship out existing stockpiles of the material.
They also want the Islamic Republic to cease operations at its Fordow uranium enrichment facility, buried deep inside a mountain near the holy city of Qom.
Iran has so far refused to do so, signaling only that it may be willing to discuss suspending higher-level enrichment if the West lifts painful sanctions on its oil and banking industries, something Western governments do not want to do as a first step.
Diplomats say they will seek answers at the meeting of technical and sanctions experts in Vienna, and at the follow-up negotiations to be conducted by senior foreign ministry officials in Geneva on November 7 and 8, on how far Iran is willing to go to allay international concerns.
"I can confirm the technical meeting on October 30 and 31 in Vienna to prepare the talks ... in Geneva," said Maja Kocijancic, a spokeswoman for European Union foreign policy chief Catherine Ashton, who oversees diplomacy with Iran on behalf of the six states.
"Experts from the EU and the six will participate."
Iran rejects accusations it is covertly seeking the means to produce nuclear weapons, saying it is refining uranium only for energy generation and use in medical treatments.
Western diplomats described last week's talks in Geneva - the first since Rouhani's election - as the most detailed and candid to date. They have signaled some flexibility on their standing offer of modest sanctions relief in return for Iranian concessions on 20 percent enrichment.
But, overall, they hope to secure a pause in the Iranian nuclear program while they negotiate a final settlement.
Iranian negotiators are keen to move quickly to secure a deal and win relief from crippling economic sanctions but Western diplomats caution there is no deal in sight yet despite a markedly warmer atmosphere in diplomacy.
Also next week, Iranian negotiators will meet inspectors from the U.N. International Atomic Energy Agency to discuss access to Iranian sites, officials and files as part of an inquiry into suspected nuclear arms-related research by Tehran.
Iran has denied engaging in any such activity.
(Editing by Mark Heinrich)