A "Plan B" to Address Iran’s Accelerating Nuclear Program

Volume 14, Issue 8
November 9, 2022

Since negotiations to restore the 2015 nuclear deal, known as the Joint Comprehensive Plan of Action (JCPOA), stalled in late August, the political space for reaching an agreement to resurrect the accord has narrowed and prospects for reviving the JCPOA have diminished. Tehran’s brutal repression of protesters following the death of Mahsa Amini and Iran’s military support for Russia’s war against Ukraine, including the illegal transfer of drones, has shifted U.S. and European focus away from the nuclear talks and increased pressure on the Biden administration to refrain from any further negotiations with the Raisi government.

Iran's ambassador to IAEA Mohsen Naziri Asl speaks during the General Conference of the International Atomic Energy Agency (IAEA) at the agency's headquarters in Vienna, Austria on September 26, 2022. (Photo by JOE KLAMAR/AFP via Getty Images)Even before the protests, Iran’s negotiating strategy jeopardized the prospects of reaching a deal to restore the JCPOA. In August, as negotiators closed in on an agreement, Tehran derailed progress with its unacceptable and unrealistic demands that the deal include a timetable for ending the International Atomic Energy Agency’s (IAEA) investigation into past nuclear activities that should have been declared to the agency and a commitment that the IAEA refrain from further investigations into Iran’s nuclear past. This ultimatum casts doubt on Iran’s commitment to resurrecting the JCPOA. As Tehran is well aware, there is no space to negotiate over the IAEA’s safeguards investigation. The United States and its JCPOA partners cannot and will not pressure the IAEA into actions that are contrary to its safeguards mandate.

From a nonproliferation perspective, however, the United States cannot afford to wait for much longer for Iran to moderate its demands over the IAEA investigation or to see how the current protests play out. U.S. Special Envoy for Iran Robert Malley made clear in an Oct. 31 event at the Carnegie Endowment for International Peace that the United States still supports restoring the JCPOA, but that talks are not the U.S. focus at this time given Iran’s negotiating position. During the stalemate, the United States continues to enforce nuclear-related sanctions, but these actions are not aimed at stabilizing the current crisis, nor can they.

The Raisi government has made clear it will continue ratcheting up its nuclear activities in response to perceived provocations from the United States and Europe, including further sanctions. The alarming growth in Iran’s nuclear program and bleak prospects for JCPOA restoration significantly increase both the threat of Iranian proliferation and the risk that at some point the United States, or more likely Israel, resorts to kinetic action to try and set back Iran’s nuclear advances in the short term.

Given these risks, it is imperative for the United States, its partners in the JCPOA, and Iran to begin thinking of steps to stabilize the current nuclear crisis. Trying to negotiate an alternative, interim deal would be time-consuming and face similar challenges to those afflicting the indirect talks to restore U.S. and Iranian compliance with the JCPOA. A more feasible approach would be to focus on reciprocal, confidence-building steps by the United States and Iran designed to prevent further escalation, reduce the risk of proliferation, and decrease the chances of miscalculation. On the nuclear side, increasing the monitoring of Iran’s nuclear program would be an ideal starting point for stabilizing the current situation. Increasing transparency would provide greater assurance that any move toward an Iranian nuclear weapon or diversion of materials and technologies would be detected more quickly and could help deter Tehran from taking such action.

Such an approach does not mean that the Biden administration and its European partners must abandon their support for the JCPOA, although restoration of that accord is increasingly unlikely. Rather, it allows the United States and the P4+1 (China, France, Germany, Russia, and the United Kingdom) to preserve space for future diplomacy to restore the nuclear deal or to negotiate a new nuclear agreement. Preventing further nuclear escalation would also benefit U.S. national security by reducing the likelihood of a nuclear-armed Iran or a military conflict to try to prevent it.

If the United States does attempt to engage with Tehran to stabilize the current nuclear crisis, the Biden administration will face criticism for undermining the protestors and legitimizing the current regime. Failure to constrain Iran’s nuclear program, however, increases the likelihood of Tehran deciding to develop nuclear weapons, particularly if it feels its regime is under threat and that external forces are responsible for or contributing to the destabilization of the state. U.S. and European involvement in the overthrow of Muammar Gaddafi in Libya and Saddam Hussein in Iraq, years after both leaders abandoned their illicit nuclear weapons programs, may suggest to Iran that a nuclear deterrent is necessary to limit foreign intervention in domestic protests. North Korea’s reliance on nuclear weapons to protect the Kim regime may further bolster the assessment in Tehran that nuclear weapons are necessary to preserve the territory and governance structure of Iran.

A nuclear-armed Iran may also be emboldened to use its deterrent to act more aggressively in the region. Russia, for example, is using nuclear threats to try to deter third-party intervention on behalf of Ukraine after President Vladimir Putin's decision to invade the country in February.

While dealing with Iran may seem distasteful, particularly now given the government’s ruthless crackdown on the peaceful protests, it is necessary. Preventing Tehran from obtaining nuclear weapons must remain an urgent policy priority precisely because of the nature of the regime and the lengths it will go to in order to retain power. Unfortunately, the time has come to begin considering alternative diplomatic actions outside of restoring the JCPOA to achieve that goal.

The Risks Posed by Iran’s Advancing Nuclear Program

Iran’s advancing nuclear program poses both short and long-term proliferation risks that will become more serious over time if the United States and its European partners do not soon pivot to a diplomatic strategy designed to stabilize the current nuclear threat. The risk of conflict also increases, as Iran may misjudge the space it has to increase leverage by expanding its nuclear program. Given the relatively muted international response to Tehran’s past escalations, such as enrichment to 60 percent, and mixed signals from the United States, Europe, and Israel over what constitutes red lines, there is a significant chance that Iran miscalculates and triggers military action.

In the short term, Iran’s ability to "breakout," or produce enough weapons-grade material for a bomb (25 kilograms of uranium enriched to 90 percent), possibly between IAEA inspections, increases the risk and likelihood of proliferation. While the United States is willing to accept the risk of undetectable breakout at this point, this calculation could change as Iran’s nuclear program advances, the prospects of a deal to restore the JCPOA diminish, or Iran perceives the benefits of nuclear weapons outweighing the costs of their development. A new, more hawkish Israeli government under Benjamin Netanyahu may also be unwilling to tolerate the low breakout window. Comments from Netanyahu and his allies in recent weeks suggest a greater willingness to use military force to set back Iran’s nuclear program.

The U.S. assessment of the proliferation threat may also change as Iran’s capacity to quickly produce material for multiple nuclear weapons increases. Currently, Iran can produce enough weapons-grade uranium for one nuclear bomb in less than a week. Israeli military officials have publicly stated that weaponization could still take another one to two years, but some experts assess that Iran could move more quickly. Regardless of the precise timeframe, Iran is likely to weaponize at a covert facility, making detection and disruption more difficult. One bomb’s worth of weapons-grade uranium, however, will have limited strategic value as a deterrent, particularly given that Iran has never conducted an explosive test of a nuclear warhead. But as the timeframe for producing multiple bombs' worth of weapons-grade uranium decreases, Iran's program poses more of a proliferation threat because the security value for Tehran increases significantly if it can build more than one bomb. It would also be more challenging to disrupt an Iranian breakout if Tehran were able to produce multiple bombs' worth of weapons grade uranium and move them to several covert sites. 

As of September, Tehran could produce enough weapons-grade uranium for an estimated three bombs in about a month. That one-month timeframe will drop further, even if Iran takes no additional action to expand its uranium enrichment capacity because Tehran continues to stockpile uranium enriched to 60 and 20 percent and install more advanced centrifuges, which enrich uranium more efficiently. The stockpiles of 60 and 20 percent uranium are particularly significant in assessing proliferation risk as material enriched to these levels can be much more quickly enriched to weapons grade.

Iran's short breakout window is not, by itself, an indication that Tehran intends to pursue nuclear weapons. It does, however, increase the likelihood of Iran deciding to do so at some point in the future, as Iran’s internal and external security environment faces new challenges. For instance, the growing perception by Iran’s current government that the regime is at risk as a result of the current protests or may be at risk down the road could make its withdrawal from the nuclear Nonproliferation Treaty (NPT) and/or possible pursuit of nuclear weapons appear more beneficial to hardline decision-makers, particularly if Tehran perceives third party states as playing a key role in supporting or instigating the protests.

Similarly, regional tensions, principally any attack on Iran’s nuclear infrastructure, could lead the regime to assess that nuclear weapons are necessary to deter future attacks. Iran’s military support for Russia’s invasion of Ukraine could also lead Tehran to gamble that Moscow would block or mitigate action by the UN Security Council if Iran were to decide to violate its international legal commitments under the NPT. Perhaps more likely, Iran may calculate that geopolitical divisions would prevent a unified international sanctions campaign against Iran, thus reducing the costs that Tehran would pay for developing nuclear weapons.

While external threats and internal dissent have been factors in Tehran’s decision-making before, Iran has never been this close to a nuclear weapon in its history. The speed at which Iran could now build a weapon will influence Tehran’s calculations, underscoring that the current proliferation risk is not sustainable.

Even if Iran’s leaders do not make the decision to pursue nuclear weapons, it appears likely that they will continue to assess that further escalation of Iran's sensitive nuclear fuel cycle programs is a sustainable form of leverage. If Iran expands its nuclear program unchecked, the development of new capabilities will have longer-term implications for the proliferation threat and raises new obstacles for future diplomacy.

There is a range of nuclear-related activities Tehran can pursue to escalate or respond to perceived U.S. provocations that will have a longer-term impact.

Iran, for instance, has publicly threatened to enrich uranium to 90 percent, the level considered weapons-grade, and considered beginning enrichment to that level in June 2022 after the IAEA Board of Governors passed a resolution censuring Iran over the safeguard’s investigation before deciding to reduce monitoring instead. The U.S. intelligence community also appears to view Iran’s threat to enrich to 90 percent as serious, noting in the 2022 Worldwide Threat Assessment that Iranian officials “probably will consider” enriching to that level if Iran does not receive sanctions relief.

While 90 percent enrichment would be one of the more significant escalations that Iran could pursue short of declaring its intention to build nuclear weapons, Tehran may gamble that producing very small quantities of 90 percent enriched uranium, or enriching to that level but not stockpiling the material, would not be enough to incite military action against Tehran. However, even the production of 90 percent in gram quantities would provide Iran with useful, irreversible knowledge applicable to weapons development, even if it does not significantly alter the current breakout.

Even if Tehran views enrichment to 90 percent as too great a risk, Iran has other options, such as expanding its advanced centrifuge work and exploring different cascade designs to increase uranium enrichment efficiency. There is also a range of weaponization-related activities that Iran could pursue while claiming the work is for civil nuclear purposes, such as expanding its uranium metal research. Uranium metal is directly relevant to pursuing an explosive device. The E3 in particular appears concerned about uranium metal activities and has warned Iran against engaging in this key area of weapons-related research.

Initiating new areas of research pose less of a short-term threat, but over the long term, as Iran masters new capabilities, these activities will alter assessments of a proliferation risk because they expand the pathways available to Iran for developing nuclear weapons. There are also implications for diplomacy. New capabilities give Iran more leverage in future negotiations and the lack of monitoring of some of these activities raises further concerns about verification down the road and reestablishing a baseline of Iran’s nuclear program.

Research and development also has implications for the nonproliferation value of the JCPOA, decreasing the likelihood that restoration of the accord will remain a viable option if the stalemate in talks continues. For instance, when Iran was fully implementing the JCPOA from 2016 to mid-2019, the time it would take to amass enough material for one bomb was about 12 months. Under a restored JCPOA, Malley told the Senate Foreign Relations Committee in May 2022 that Iran’s breakout would be reduced to about six months—now probably closer to four-five—because of the irreversible knowledge Iran has gained and its development of advanced centrifuges. As a result, the Biden administration may soon assess that the nonproliferation benefits of the JCPOA are no longer worth the sanctions relief Tehran will receive in the return.

The Growing Monitoring Gap

Compounding the proliferation risks posed by Iran’s nuclear program is the growing monitoring gap. The lack of transparency regarding Iran’s nuclear activities has a negative impact on crisis stability and will make future diplomacy more challenging.

Currently, Iran is subject to minimal IAEA monitoring. Iran is implementing a comprehensive safeguards agreement, as required for all non-nuclear weapon states party to the NPT, but history has demonstrated that comprehensive safeguards are insufficient for preventing determined proliferators. Under the safeguards agreement, the IAEA continues to access Iranian facilities where nuclear materials are present, such as the Natanz and Fordow enrichment facilities and the Isfahan fuel fabrication site. The frequency of inspections at those facilities is based on several factors, including enrichment levels, so Tehran is subject to more inspections now that it is enriching to 60 percent. But even with more frequent inspections, a comprehensive safeguards agreement is insufficient for providing assurance in the long run that Iran’s nuclear program is entirely peaceful. The risk remains that Iran could try to produce enough weapons-grade material between IAEA inspections and divert materials, such as centrifuges, from facilities where the agency is not currently conducting inspections.

When the JCPOA was fully implemented, Iran’s nuclear program was subject to the most intrusive verification regime ever negotiated. Several key sites were subject to continuous surveillance and inspectors had greater access to Iranian nuclear facilities, including sites where nuclear material was not present. Furthermore, unlike many restrictions in the JCPOA, the most crucial element of that monitoring regime, Iran’s application of more intrusive IAEA safeguards known as the additional protocol, does not expire.

However, as part of its response to the U.S. pressure campaign, Iran halted the implementation of the additional protocol and other JCPOA-specific monitoring measures in February 2021. As a result, the agency has not inspected certain facilities integral to the country’s nuclear program, such as its centrifuge production sites and uranium mines and mills, for 20 months. IAEA cameras did continue to collect data from some of these locations and Tehran says it will give the surveillance recordings to the agency in the event of a deal to restore the JCPOA, but many of these cameras have been unplugged since June 2022. Iran disconnected the cameras at that time in response to the IAEA Board of Governors passing a resolution censuring Iran for failing to comply with the agency’s safeguards investigation. Further complicating the gaps in monitoring is Iran’s development of new nuclear facilities since February 2021 that are not covered by the existing safeguards agreement, such as Iran’s new centrifuge production workshops, and therefore are not being inspected. The IAEA will likely have less clarity about the capabilities and capacities at these locations if the JCPOA is restored or a new deal is reached because of the gaps in access.

As a result of the reduction in monitoring, IAEA Director General Rafael Mariano Grossi warned in September 2022 that the agency will face “considerable challenges” in confirming Iran’s declared inventory of centrifuges and heavy water, even with Tehran’s full cooperation. The longer this gap remains, the more difficult it will be for the agency to reconstruct an accurate history of Iran’s nuclear activities during the monitoring gap.

Any doubt about the baseline will drive speculation that Tehran has diverted materials for covert purposes and could make it more challenging for the United States to assess, as required under the Iran Nuclear Agreement Review Act (INARA), whether the IAEA can monitor a future nuclear deal.

The reduction in monitoring also increases the risk of a premature use of force to set back Iran’s nuclear program. The United States and Israel, the two countries most likely to use force, might be willing to tolerate certain nuclear escalations or the continuation of current activities if there were additional verification mechanisms in place that would more quickly detect any move to try to build nuclear weapons or further increase its enriched uranium stockpiles. For instance, the risk posed by Iran’s stockpile of uranium enriched to 60 percent might be more manageable if inspectors had daily access to uranium enrichment facilities or if Iran’s enrichment was monitored in real time again.

Enhanced Monitoring as a Stabilization Step

Given Iran’s current breakout time, the risk of Iran crossing a U.S. or Israeli redline as it attempts to build leverage, and the monitoring gap’s negative implications for diplomacy in the long run, the United States and its P4+1 partners should focus on increasing transparency as the first step in stabilizing the current situation.

Ideally, additional monitoring mechanisms should be aimed at two objectives: 1) providing greater assurance that any attempt by Iran to breakout will be detected more quickly and 2) providing greater assurance that Iran is not diverting materials from sites that are no longer subject to inspections or surveillance.

In the short term, addressing these two objectives should help reduce the threat of proliferation and the risk of premature military action to prevent it. Increased monitoring also helps address longer-term proliferation risks by providing additional insight into nuclear activities not currently monitored and could make it easier for the IAEA to reestablish a baseline on Iran’s nuclear program. Verification activities as a stabilizing step may also be more feasible politically on the Iranian side as it does not require Tehran to halt or roll back any nuclear activities or give up what it perceives as its strongest source of leverage: its HEU stockpiles.

The most straightforward option for addressing these objectives would be for Iran to resume the implementation of its additional protocol. To distinguish reapplying the additional protocol from Iran’s actions under the JCPOA, Iran could agree to voluntarily implement the agreement as it did from 2003-2005. This would be a step below the provisional implementation required by the JCPOA. Given that more than 130 countries implement additional protocols, the Raisi government could reply to domestic criticism by arguing that it is conforming with the best practices of responsible nuclear states and not subjecting Iran to unique restrictions.

However, even if this step were to be politically feasible in Tehran, Raisi would likely demand a higher price for reapplying the additional protocol than the United States would be willing to pay. The December 2020 law required Iran to suspend the more intrusive safeguards if the parties to the JCPOA “fail to normalize banking relations, completely remove export barriers, allow complete sale of Iranian oil and petroleum products, and complete and rapid return of foreign exchange [to Iran] from the proceeds of the [oil] sales.“ If Tehran tries to tie the resumption of the additional protocol to these demands, the cost will be too high for the United States, as Washington will also seek to retain its most valuable sources of sanctions leverage for future diplomacy.

There are, however, creative solutions that would increase transparency and may be more feasible from a political perspective than reapplying the additional protocol. To address the first objective, more rapid detection of breakout, the United States and its partners could press Iran to resume real-time enrichment monitoring as a confidence-building step. Reconnecting the monitors, known as OLEMS, would provide further assurance that any move to enrich to levels greater than 60 percent would be quickly detected. Without the OLEMS in place, traditional methods of sampling and analyzing enrichment levels can take three weeks or longer, according to the IAEA. During that window, Iran could produce enough weapons-grade material for a bomb and divert it.

Other measures that could be considered include resuming daily IAEA access to Natanz and Fordow, which would provide more assurance that Tehran will not try to breakout between inspections. Iran could also move greater portions of its stockpiles of HEU away from the enrichment sites. The material would still be under IAEA safeguards and returning it to Natanz and Fordow would put additional time on the clock and raise questions about whether Iran intended to further enrich the material.

To address the second objective, deterring diversion, one option would be for the United States and its P4+1 partners to propose that Iran turn the cameras back on at some, or all, of the facilities subject to continuous surveillance under the JCPOA. Prioritization should be given to resuming monitoring of certain facilities, such as centrifuge production workshops and facilities with source materials such as uranium conversion facilities, which pose more of a proliferation risk, as opposed to facilities such as Iran’s heavy-water production plant, which is less of an immediate concern. Tehran could turn over recordings from these cameras regularly, perhaps quarterly to coincide with the IAEA’s regular reports on Iran’s nuclear program, to help ensure there has been no diversion of nuclear material from these locations. Turning over the recordings regularly would also help demonstrate Iran’s commitment to a peaceful nuclear program.

Another option would be for Iran to allow the IAEA to conduct technical visits to certain facilities that inspectors can no longer access. These voluntary, technical visits agreed to by the state have been used in the past when the IAEA has sought inspections beyond what is permitted under a comprehensive safeguards agreement but where the agency did not want to pursue special inspections. If Tehran were to agree to negotiate technical visits for inspectors regularly it could assist the IAEA’s efforts in re-establishing a baseline down the road and it increases the likelihood that any diversion of materials from the currently unmonitored facilities would be detected.

Focusing on monitoring and verification as an initial, stabilizing step also provides benefits for Iran. First, allowing additional monitoring and verification would support Iran’s assertion that its nuclear program is peaceful and that it has no intention of pursuing nuclear weapons. The added transparency could also be useful in pushing back against speculation that Iran intends to use the impasse in negotiations to restore the JCPOA to buy time to build up its nuclear program before deciding to build nuclear weapons and/or to siphon off materials for undeclared nuclear activities.

Second, monitoring and verification reduce the risk of the United States and/or Israel miscalculating the risk posed by Iran’s nuclear activities and prematurely using force to try and roll back Tehran’s nuclear program. These strikes would be very costly to Iran and put at risk the lives of Iranians working at these facilities. Any resort to force would also only set back Iran’s nuclear program temporarily and is likely, in the long run, to spur further nuclear advances. It could also escalate to a broader conflict.

Third, greater transparency now increases the likelihood that the IAEA will be able to reconstruct a record of Iran’s nuclear activities. The IAEA’s ability to reestablish a baseline and verify the inventory of certain materials related to Iran’s nuclear program could have an impact on future negotiations, particularly given that under INARA the U.S. administration must provide to Congress an assessment of the IAEA’s ability to verify any deal with Iran. Any perception that the IAEA will not be able to monitor an agreement will negatively impact Congressional support for an accord. So, if Iran wants to keep open the option of receiving sanctions relief, it behooves Tehran to recognize the benefits of increasing monitoring now.

In exchange for Iranian actions to enhance monitoring, the United States and its P4+1 partners could offer relief from specific sanctions, perhaps including limited oil sales to Europe. This would provide Iran with some benefits and could also mitigate the gap in European energy supplies caused by Russia’s invasion of Ukraine. The United States could also look at sanctions relief that would have positive humanitarian impacts and could be quickly reversed if Iran were to stop voluntarily implementing the monitoring measures or the release of set amounts of Iranian frozen assets.

If both the United States and Iran take these actions on a voluntary reciprocal basis, the Biden administration could argue that this does not constitute a deal and is not subject to review by Congress under INARA. But even if the Biden administration decides not to make that case or is persuaded that Congress should review these stabilization steps, there is a strong argument that members should support the administration’s actions as an interim step to increase the prospects for a future deal. Failure to prevent nuclear escalation will also likely have negative consequences for U.S. national security and increases the risk of the United States becoming embroiled in another conflict in the Middle East, a conflict that Washington can ill afford at this time.

If these initial, reciprocal steps are successful, the United States and the P4+1 could consider some further corresponding steps that would reduce proliferation risks. This would be particularly beneficial if the United States and Iran decide not to restore the JCPOA and instead pursue negotiations on a new agreement. In that case, creating time and space for prolonged talks by reducing the most imminent threats would increase the likelihood of a successful deal. On the nuclear side, this could include a commitment from Iran to refrain from new research and development activities and/or capping its stockpiles of 60 and 20 percent enriched uranium. This approach would allow Iran to maintain what it views as its most significant source of leverage while preventing Iran’s breakout for subsequent significant quantities of nuclear materials from further diminishing.


Nearly two years have passed since the Biden administration took office and set out to negotiate terms with Iran to restore mutual compliance with the JCPOA. The 2015 deal remains the best path forward for both parties, but Iran's impractical demands on issues outside the scope of the JCPOA have stymied progress. Now, the Raisi government's brutal crackdown on growing protests against the regime and its military support for Russia severely complicate the path to restoring the JCPOA. Meanwhile, Iran continues to expand its nuclear program, increasing the proliferation risk and the potential for a military conflict.

Given the current challenges that the United States is facing in confronting Russian aggression against Ukraine and countering China’s regional ambitions, Washington can ill afford to be drawn into a conflict with Iran, nor can the United States and the international community afford to see Iran, possibly emboldened by its nuclear weapons capability, become more aggressive in the region and even more repressive domestically.

As a result, it is necessary to explore options designed to stabilize the current nuclear crisis by increasing monitoring of Iran’s nuclear program. Such an approach is not a long-term solution or a substitute for a comprehensive agreement that blocks Iran’s pathways to nuclear weapons, but it is necessary to prevent further deterioration of an already worrisome situation that was triggered by the United States' disastrous 2018 decision to withdraw from the JCPOA. The United States can and must remain focused on a comprehensive diplomatic solution to roll-back Iran's dual-use nuclear activities. But to create the time and space for negotiations the United States and its partners must act now to try to stabilize the current crisis before it is too late.