World powers, Iran race to conclude nuclear deal as deadline looms

Khamenei also suggested that sanction relief could not wait until the International Atomic Energy Agency verifies Iranian compliance with its obligations, which is at odds with the P5+1 understanding. He added that Iran would not accept curbs on research and development of more advanced machines to enrich uranium. The impending agreement restricts R&D and installation of advanced centrifuges for at least a decade, a time frame that Khamenei suggested was unacceptable in his speech.

But some analysts are quick to point out that other supposed red lines that Khamenei drew in recent months have faded — for example, a demand that Iran possess 190,000 centrifuges, enough to provide fuel for its sole power reactor at Bushehr, by 2021, when a contract with Russia runs out.

He also permitted negotiators to reach agreement on parameters for the comprehensive deal on April 2 after repeatedly opposing a two-step process and demanding that no concessions be made except in a final accord.

Ellie Geranmayeh, an Iran expert at the European Council on Foreign Relations, said that Khamenei’s latest remarks, while “unhelpful,” were probably an attempt to bolster Iranian negotiators in the aftermath of a contentious meeting Monday between Foreign Minister Javad Zarif, Iran’s chief negotiator, and French Foreign Minister Laurent Fabius, “who has also taken a maximalist public position on the contours of the deal.” 

“The stakes are too high for Khamenei to risk losing the blame game at this stage,” Geranmayeh added. “If Iran gets blamed for failure at this stage, it gets nothing, and I think the leadership knows that.”

The Iranian public is decisively backing (PDF) an agreement, and the regime risks popular protests if it walks away from Iran’s best chance for significant sanction relief. Even the conservative-dominated Iranian parliament has approved legislation that essentially transfers its review power to Iran’s national security council, where supporters of pragmatic President Hassan Rouhani hold sway.

In his remarks, Khamenei — the ultimate decider in Iran — may have been seeking to increase Iranian leverage in the final phase of the talks and to counter domestic pressure on the U.S. side. Sensing that this is their last chance to influence the talks, groups such as the American Israel Public Affairs Committee and United Against a Nuclear Iran have taken out expensive newspaper ads and pressed congressional offices with demands for Iranian concessions that Tehran has made clear it will not accept.

Proponents of a possible accord concede that it will be far from perfect. Iran will be allowed to continue to enrich uranium at Natanz and will be left in possession of its other nuclear facilities, including a deeply buried site at Fordow and a heavy water reactor under construction at Arak. However, these sites will be modified in such a way that Iran would find it extremely difficult to break out and accumulate enough fuel for a bomb for at least a decade.

According to the parameters agreed to in April in Lausanne, Switzerland, the number of centrifuges at Fordow will be cut from 3,000 to 1,000 and will not be used to enrich uranium. The main enrichment plant at Natanz will mothball all but 5,000 of its 19,000 centrifuges, and Iran will reduce a stockpile of about 8,000 kilograms of low-enriched uranium to 300 kilograms — far too little to make a weapon even if further enriched.

Furthermore, the Arak facility will be reconfigured so that it produces only a minute amount of plutonium, another potential bomb fuel, and Iran will implement the Additional Protocol of the Nuclear Non-Proliferation Treaty to provide increased access to nondeclared sites suspected of illicit activity.

Those close to the talks say the final differences are over the schedule for sanctions relief and the procedure for gaining International Atomic Energy Agency access to nondeclared sites, especially military ones. Final compromises will likely await the anticipated arrival in Vienna of U.S. Secretary of State John Kerry and his diplomatic counterparts later this week.

At an event at the Atlantic Council, a Washington think tank, last month, French Ambassador to the U.S. and former nuclear negotiator Gerard Araud predicted sleepless nights and melodrama as the talks reach a climax. He also said it was likely that the June 30 deadline will slip a bit.

Critics argue that the negotiators should threaten to tighten sanctions if Iran does not accept all their demands. U.S. and European officials counter that the sanctions regime — which they say helped elect Rouhani and bring a more skillful and flexible Iranian team to the negotiating table — has peaked and cannot be augmented in a meaningful way, absent a major Iranian provocation.

"If we were to walk away or if the Congress was to make it impossible for the agreement to be implemented ... I think the international community would be pretty reluctant, frankly, to contemplate a ratcheting up further of the sanctions against Iran,” British Ambassador to the U.S. Peter Westmacott said last month.

“My sense is that we're probably not far away from the high water mark of international sanctions against the Iranian economy,” he added.