Another possible explanation is that the apparent discrepancies between the Leader’s public comments and solutions already reached are part of a coordinated negotiating strategy in which the Iranians first re-open areas of agreement and then eventually return to the original agreements in exchange for P5+1 concessions on remaining unresolved issues.

It is also possible that Khamenei calculates that a tough public stance is temporarily necessary to placate Iranian critics of the deal but is ultimately prepared to stand by the concessions that will be required to conclude an agreement.

And of course, it is also possible that, confronted by strong domestic criticism of the Lausanne framework, the Supreme Leader has decided to walk back earlier concessions and re-draw his redlines. Whatever the explanation or combination of explanations, the public pronouncements coming from Tehran do not augur well for the negotiations. To get a deal, Iranian negotiators will have to re-commit to everything they have already accepted, even if doing so seems inconsistent with public expectations generated by the Leader’s statements. To compensate, Iran’s negotiators may feel compelled to take rigid positions on some of the critical issues left unresolved in the Lausanne framework.

Difficult Issues Remain

Perhaps the most difficult unresolved issue involves the question of past Iranian activities believed to be related to the development of nuclear weapons. The P5+1 have proposed a list of steps Iran would need to take to address international concerns about those activities. An important component on that list is a series of interviews by the IAEA of Iranian scientists and other individuals believed to have participated in the suspect activities. But the Supreme Leader has staked out an uncompromising public position that Iran’s nuclear scientists cannot be interviewed by the IAEA. Continuing to hold key participants in those activities off-limits to the IAEA can only reinforce the impasse on one of the most important issues remaining in the negotiations. Iranian officials claim that there are other means of resolving the question of past nuclear activities, but such means have not been identified, at least not publicly.

In addition to tackling the major outstanding issues, the negotiators also need to agree on a huge number of technical details required to implement the agreement. The P5+1 have proposed three lengthy technical annexes to the basic political agreement. The Iranians have tended to resist highly detailed annexes, maintaining that the necessary details can be worked out in the course of implementation. But the P5+1, especially the United States, insist that details need to be nailed down now to avoid implementation problems later.

Take More Time if Necessary

Given the significant issues still unresolved as well as the crucial technical details still to be agreed, it is very hard to imagine that a satisfactory comprehensive agreement can be achieved by the June 30 expiration of the Joint Plan of Action, the current interim agreement. Indeed, Iran may be counting on the fast-approaching June 30 terminal date to put pressure on the United States to make concessions on unresolved issues and settle for less detailed technical annexes.

There are arguments for getting the job done by the end of this month. Critics might claim that any extension would enable Iran to “play for time,” and support for imposing new legislative sanctions could be revived. Advocates of an agreement might assert that another extension would risk allowing the current opportunity for an agreement to slip away.

But meeting U.S. requirements for a sound agreement is clearly more important than meeting a self-imposed deadline. Even Congressional skeptics of the negotiations would presumably prefer to take the additional time needed to achieve an effective agreement rather than be pressured to make unwarranted concessions under artificial time pressure.

Indeed, it is Iran, not the United States, that should feel pressure to finish this month. It is Iran that continues to suffer under sanctions and the Iranian people who are impatient for economic recovery and an end to their pariah status. And it is Iran whose nuclear program remains frozen in virtually all consequential respects. The United States can well afford to take the additional several weeks, or even several months, to ensure that its requirements are met.

With U.S. Resolve, the Choice Will Be Iran's

The negotiators have come close to agreement. But a final deal could still prove elusive. Perhaps the biggest risk of failure is an Iranian miscalculation that the Obama administration is so committed to an agreement, and so eager for one, that it is prepared to conclude the negotiations largely on Iran’s terms. President Obama clearly wants an agreement, but he and his administration have a definite idea of the kind of agreement they can support. They need to make clear that, if Iran cannot accept such an agreement, they are prepared to walk away.

The choice will then be up to Iran, especially to the Supreme Leader. He will finally have to get off the fence and authorize his negotiators to accept the solutions necessary to conclude the deal (including some he has recently and strongly criticized). He can no longer have it both ways, giving general, rhetorical support to his negotiators but publicly articulating redlines that make their job difficult. Unless he throws his weight clearly behind an agreement, the best opportunity for a peaceful solution to the Iran nuclear issue will be missed.    

Robert Einhorn is a senior fellow at the Brookings Institution. From 2009 to 2013, while serving as the State Department’s Special Advisor for Nonproliferation and Arms Control, he was a senior member of the U.S. delegation to the Iran nuclear negotiations.

Image: Office of the Supreme Leader