With nuclear negotiations between Iran and the 'P5 plus 1' group of world powers resuming this week, analysts following the talks say the political will among the parties to sign a final framework for a détente has - for the time being - remained.
Moving forward, the challenge lies in how to reconcile the differences in perceptions and expectations between Iran and the 'P5 plus 1' - the United States, France, Russia, Britain, China and Germany - in order to arrive at a nuclear agreement that negotiators can present to critics, especially in Washington and Tehran, without looking weak back at home.
Observers say the fundamental disagreements that halted the positive momentum of the most recent negotiations weren't simply over straight "numbers", such as the number of centrifuges Iran will finally have or the final length of time allowed for a "breakout", which is the time Iran would need to produce enough highly enriched uranium for a bomb.
Such sticking points are considered a normal part of the negotiations and are ultimately resolvable, says veteran diplomat Roberto Toscano, who served as Italy's ambassador to Iran from 2003 to 2008.
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From Tehran's standpoint, the major obstacles leading to the failure of the Vienna talks, which concluded with a seven-month extension, were ostensibly the same as they were going in.
Namely, how substantial - and how permanent - will sanctions relief actually be if Iran substantially reduces its uranium enrichment programme and yields to years of unprecedentedly intrusive nuclear inspections.
"It's the asymmetry that is very hard to swallow, mainly for political reasons, in Tehran," says Ambassador Toscano. "A parallel acceptance of graduality … is not there now. It's like asking you to deliver now, and saying you'll be paid for it later in instalments. That's not only asymmetric … it's humiliating."
Though Iran has always said publicly the absolute lifting of all sanctions is the "minimum expectation" for the outcome of nuclear talks, officials admit - in private - they're aware that major sanctions relief will take time.
Sanctions relief has long been expected to happen in stages, as a function of steady IAEA verification of Iran's compliance with each component of a final deal.
The complex nature of US treasury sanctions legislation in particular, which can't actually be lifted without an act of Congress, means initial relief will likely start with presidential waivers and be subject to periodic renewal.
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The most critical sanctions impacting Iran are financial sanctions that have locked Iran out of the global banking system and barred Tehran's access to most of its foreign exchange holdings.
Together with a European oil embargo and US sanctions penalising purchasers of Iranian oil, these sanctions have cut Iranian oil sales by over 50 percent and helped slash the value of Iran's national currency.
They've also helped keep out key technologies and up to $300bn dollars in foreign investments which Iran needs to develop its underdeveloped ailing energy sectors.
Since the interim Joint Plan of Action (JPA) kicked off in January, Iran has been able to access a total $7bn of an estimated $100bn in foreign exchange reserves currently locked up in international bank accounts.
Tehran will be allowed to access $700mil of these assets per month for the duration of the latest extension, which ends June 30. Limited sanctions relief allowed by the JPA will also remain in effect.
In exchange,Tehran is expected to take some steps including reducing an additional 35kg of its remaining 75kg stockpile of 20 percent uranium oxide, and allowing the IAEA to access Iran's centrifuge production centres more often and for snap inspections, according to International Crisis Group's senior Iran analyst, Ali Vaez, who was in Vienna during last month's talks.
In Tehran, analysts say the outcome of the nuclear talks is being considered a measure not just of the Islamic Republic's standing in the world at large, but also among its neighbours in the Middle East.
The problem is that there is no trust whatsoever between the US and Iran. So it is understandable why the US wants intrusive inspections and Iran wants rapid removal of all sanctions. For Iran, especially the Revolutionary Guard Corps (IRGC), the concessions that the US seeks present a difficult face-saving dilemma in the Middle East context.
Given the international community's general lack of trust in Iran, which in the past has concealed the degree and nature of some of its nuclear activities, confirming Iran's transparency will require a level of on-the-ground inspections inside the country that is historically unprecedented, according to Hossein Askari, an economist who holds the Iran chair at George Washington University.
Such intrusive inspections pose a dilemma for Ayatollah Ali Khamenei, who is widely known for his own distrust of the US and suspicions that Washington will try to expand negotiations beyond Iran's nuclear file.
They also pose a problem for the rest of Iran's ruling elite, who are keen to maintain Tehran's reputation as a power player among its regional neighbours and want to avoid the image of capitulation.
Without some hefty sanctions relaxation promised up-front for Iran's government to present to its public as a meaningful sign of additional relief in the years to come, it will be very difficult for leaders to publicly justify such intrusive verification measures.
"The problem is that there is no trust whatsoever between the US and Iran. So it is understandable why the US wants intrusive inspections and Iran wants rapid removal of all sanctions," says Askari.
"For Iran, especially the Revolutionary Guard Corps (IRGC), the concessions that the US seeks present a difficult face-saving dilemma in the Middle East context."
For the time being, Iran's president and nuclear negotiating team have sought to galvanise support for more talks, spinning a positive view of the recent extension in the face of conservative lawmakers already complaining that President Hassan Rouhani's team has yielded too much in negotiations.
"A comprehensive general agreement is inevitable," says Saeed Laylaz, a Tehran-based analyst close to the Rouhani administration.
"Two years ago, nobody would have been able to believe that Iran's foreign minister will negotiate with his US counterpart for several hours a day. We are at the beginning of a different age and a different decade for Iran."
In televised remarks to the nation after talks ended, Iran's president vowed to never abandon the country's right to nuclear technology, saying that more talks would eventually lead to a deal and sanctions would be lifted "step by step".
In his first comments after the November 24 negotiations, Iran's supreme leader also indirectly endorsed the extension of the talks, even as he lambasted the US and "European colonialist countries" for trying to bring the country to its knees.
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"If the 'P5 plus 1' was just negotiating with Rouhani and [chief Iranian negotiator Mohammad Javad] Zarif, then things would be easier, but they have to go back to Khamenei and whoever else they need to answer to in that conservative camp," says Alireza Nader, a senior policy analyst at the RAND Corporation.
"Khamenei has allowed the negotiation to go forward, but how flexible is he?"
Laylaz insists Khamenei strongly supports the negotiations. Such blatant involvement by the Islamic Republic's supreme leader, who has final say in all matters of state, in the current nuclear discussions indicates that Tehran's negotiators have his approval and their final commitments will be accepted by known hardliners back in Tehran. "Both sides need some time," Laylaz says.
Back in Washington, where congressional Republicans are slated to take control of the Senate in January, US policymakers have said they will be closely eyeing the timeline and progress of the extended nuclear talks, and will vie to insert greater congressional oversight over their resolution.
"It really comes down to the supreme leader's calculation of risk. Khamenei is also being lobbied by the IRGC and hardliners," Gary Samore, Obama's former White House coordinator for arms control and weapons of mass destruction, said at a panel in Washington the day after talks ended.
"To the extent we can influence Khamenei's calculations; we have to convince him that we are prepared to walk away from these negotiations."
Source: Al Jazeera