Nuclear Diplomacy with Iran: Challenges and Future Prospects
Iran Talks. Abschluss Iran Verhandlungen. UNO. Wien, 14.07.2015, Foto: Dragan Tatic

Nuclear Diplomacy with Iran: Challenges and Future Prospects

The Iran nuclear agreement, formally known as the Joint Comprehensive Plan of Action (JCPOA), is a landmark accord reached between Iran and several world powers, including the United States, in July 2015. Under its terms, Iran agreed to dismantle much of its nuclear program and open its facilities to more extensive international inspections in exchange for billions of dollars’ worth of sanctions relief.

However, the deal has been in jeopardy since President Donald J. Trump withdrew the United States from it in 2018. In retaliation for the U.S. departure and for deadly attacks on prominent Iranians in 2020, including one by the United States, Iran has resumed some of its nuclear activities. President Joe Biden has said the United States will return to the deal if Iran comes back into compliance, but analysts say that renewed diplomacy would have to overcome major political hurdles. And a revival of Iran’s nuclear weapons program would dramatically escalate tensions in the Middle East, they say, raising the prospects for conflict between Iran and its regional rivals, including Israel and Saudi Arabia.      


The JCPOA, which went into effect in January 2016, imposes restrictions on Iran’s civilian nuclear enrichment program. At the heart of negotiations with Iran were the five permanent members of the UN Security Council (China, France, Russia, the United Kingdom, and the United States) and Germany—collectively known as the P5+1. The European Union also took part.

Some Middle Eastern powers, such as Saudi Arabia, said they should have been consulted or included in the talks because they would be most affected by a nuclear-armed Iran. Israel explicitly opposed the agreement, calling it too lenient.


Iran and six world powers known as the P5+1 (China, France, Germany, Russia, the United Kingdom, and the United States) reached a historic nuclear deal on July 14, 2015 that limited Iran’s nuclear program and enhanced monitoring in exchange for relief from nuclear sanctions. Prior to that, Iran had been engaged in efforts to acquire the capability to build nuclear weapons for more than two decades. Although it remained uncertain whether Tehran would have made the final decision to build nuclear weapons, it had developed a range of technologies, including uranium enrichment, warhead design, and delivery systems, that would give it this option in a relatively short time frame. Tehran maintains that its nuclear activities are entirely peaceful.

Iran had previously agreed to forgo the development of nuclear weapons as a signatory to the Nuclear Nonproliferation Treaty, which has been in force since 1970. However, after the overthrow of the Pahlavi dynasty in 1979, Iranian leaders secretly pursued this technology. (In 2007, U.S. intelligence analysts concluded that Iran halted its work on nuclear weapons in 2003 but continued to acquire nuclear technology and expertise.) 


Nuclear Diplomacy with Iran: What’s Ahead for the Biden Administration?

Of all the pressing issues in the volatile Middle East—wars in Syria, Yemen and Libya, unstable Iraq, imploding Lebanon, and the 10,000 ISIS fighters and other al-Qaida franchises still on the loose—the most pressing for President-elect Joe Biden will be Iran’s controversial nuclear program. He has repeatedly promised to rejoin the nuclear deal, brokered by the world’s six major powers in 2015, which Donald Trump pulled out of in 2018.

President Hassan Rouhani of Iran has a vested interest in reviving diplomacy but has limited time to engage the Biden administration with elections in Iran slated for June (Brittainy Newman/The New York Times).

But, the Biden administration won’t have much time—maybe six to eight weeks—to make initial progress. Iran shuts down for two weeks on March 20, for Nowruz, the Persian New Year, and the presidential campaign starts when it opens up again in April. The election is on June 18. President Hassan Rouhani, who dared to run in 2013 on a platform of diplomacy with “the Great Satan” and limits on Iran’s nuclear program, will not be a candidate; Iran has a two-term limit. Rouhani has a vested interest in reviving diplomacy that could ease some sanctions and restore his legacy, but he has limited time to engage with the Biden administration before he is a lame duck.

The stakes are broader than Iran’s nuclear capability. The Trump administration’s “maximum pressure” campaign—sweeping sanctions that have isolated Iran financially and targeted top politicians, the military and more than a dozen banks—have given leverage to hardline “principlists” and conservatives, who won the majority of seats in February 2020 parliamentary elections. They will use the economic costs and failure of diplomacy with the U.S. as a central plank in their platform to take back the presidency.

After a new Iranian president is inaugurated in August, the most difficult step will be broader reengagement on all the other issues that the United States has long wanted to address, including Iran’s missile program, regional influence, support for terrorism, and human rights abuses.

For Biden, it’s not just about rejoining the nuclear deal. As Trump ramped up sanctions, Iran engaged in a series of breaches of the nuclear deal that increased its production and stockpile of uranium enrichment, the fuel used for both peaceful nuclear energy and the world’s deadliest weapon. In an essay for CNN, in September, Biden proposed “compliance for compliance”—which would include Washington rejoining the deal and Tehran reducing its materiel. But who goes first? What sanctions should the United States lift and which should remain? How much does Iran undo? Ultimately both sides want leverage over the other.

The first challenge will be agreeing on the roadmap for diplomacy, quickly. The second step will be taking substantive steps to avoid diplomacy from becoming an election football that defines who wins Iran’s presidency. Down the road, after a new Iranian president is inaugurated in August, the third and most difficult step will be broader reengagement on all the other issues that the United States has long wanted to address, including Iran’s missile program, regional influence, support for terrorism, and human rights abuses. Biden will be the eighth U.S. president since the 1979 revolution to try to defuse tensions with Iran. Four years may not be enough time to deal with four decades of flashpoints between Washington and Tehran.

Challenges to the nuclear deal

Given the current climate in the wider Middle East, Iran is certainly feeling the pressure. Talk of military strikes by both the US and Israel, coupled with the presence of US troops on Iran’s borders as well as in the Persian Gulf, have undoubtedly put it in an uncomfortable position. Feeling threatened and being under constant scrutiny can only add to its insecurity.

Since the creation of the Islamic Republic of Iran in 1979, its relations with both its neighbours and the West have been tumultuous. Faced with a WMD-capable (Weapons of Mass Destruction-capable) Iraq, an unstable region and a lack of international support, Iran has felt politically isolated, insecure and, above all, threatened.

Twenty-seven years later, however, much has changed in Iran’s favour: Saddam Hussein’s regime has been toppled and there appears to be no real threat from the new Iraqi government. Tehran has many friends in the new Iraq and can certainly influence developments beyond its borders – for better or worse.

More recently, Iran has established better relations with most of the states within the region (with the exception of Israel) and improved economic ties with China, India, Russia and the EU itself. Nevertheless, the region is still unstable and volatile.

There are, in other words, reasons why Iran would want to have a nuclear weapons capability. Going nuclear could be in its national interest because of its need to feel secure in a highly unstable region, the sense of prestige which comes from having a nuclear weapons capability, and the need to counter possible threats. Recent developments in strategic affairs – from North Korea to India – also seem to prove that having nuclear weapons does make a difference.

In the aftermath of the JCPOA, during the remainder of President Obama’s second term and despite the efforts of Secretary of State John Kerry, major international banks remained hesitant to facilitate trade agreements with Iran for fear of violating stillexisting US sanctions. Moreover, a US Supreme Court ruling confiscating $2 billion of Iranian money, a new visa waiver law that discriminated against travel to Iran, and many pieces of legislation in Congress seeking to impose new sanctions spurred further distrust and suspicion among Iranians and the international community (Hurley, 2016). Since the implementation of the nuclear deal in January 2016, the US Congress and both the Obama and Trump administrations have continuously imposed sanctions citing as their justifications human rights concerns, terrorism, missile tests, and regional differences. In November 2016, the US Senate unanimously voted to extend the Iran Sanctions Act for 10 years. Iranian authorities slammed this action as a blatant violation of the JCPOA and vowed to respond to it (Varzi, 2016).

Prospects for the Iran nuclear deal

As United States President-elect Joe Biden prepares to take office on 20 January 2021, a top foreign-policy priority – to the extent that domestic troubles allow room for a foreign focus – will be to return the US to the 2015 Joint Comprehensive Plan of Action (JCPOA), known as the Iran nuclear deal. During the election campaign, Biden said he would do so if Iran returned to compliance with the nuclear limits that the deal established. Biden would then use this as a basis for engaging in wider talks with Iran on other issues of concern. Whether even the first part of his ambitious plan to restore comity to US–Iran relations will be possible, however, depends on political dynamics in Iran and within the US Congress.

Biden laid out his plan for relations with Iran in a 13 September written commentary via CNN. Castigating President Donald Trump for a failed ‘maximum pressure’ policy that ‘worsened the threat’ from Iran and failed to win the support of a single US ally, Biden made a three-part promise. Firstly, like every incoming US president this century, he pledged to prevent Iran from acquiring a nuclear weapon. The second promise involved a package of diplomatic measures. Biden would rejoin the nuclear accord ‘if Iran return[ed] to strict compliance’ with the deal. Relatedly, he would work to strengthen and extend the JCPOA’s provisions, while also addressing other issues of concern, among them freeing Americans detained in Iran, condemning Iranian violations of human rights, and helping US regional partners reduce tensions and end regional conflicts, including the war in Yemen.

The diplomatic track would also include steps to ensure that US sanctions did not hinder Iran’s fight against COVID-19 and an early repeal of Trump’s ban on travel to the US from several Muslim-majority states, the biggest impact of which was felt by Iranian citizens.

The third part of Biden’s plan is to counter Iran’s ‘destabilizing activities’, working closely with Israel and using targeted sanctions against ‘Iran’s human rights abuses, its support for terrorism’ and its ballistic-missile programme. These efforts would be made on a parallel track unconnected to nuclear negotiations. Biden said he would be prepared to defend vital US interests and US troops, but was ready to ‘walk the path of diplomacy if Iran takes steps to show it is ready too’.

Compliance for compliance

Biden’s return to the JCPOA would entail a restoration of the sanctions relief that president Barack Obama’s administration provided in 2016. Trump reversed those measures in May 2018 under executive action and by June 2020 had stopped issuing sanctions waivers altogether. No Congressional action was involved. Biden can thus use his own executive authority to undo Trump’s moves, including new sanctions that Trump imposed, such as his blacklisting of the Central Bank of Iran and key Iranian officials. Under the Iran Nuclear Agreement Review Act of 2015, however, Biden would need to certify every 90 days that Iran was in compliance with the JCPOA. That legislation, and the domestic US politics surrounding the nuclear accord, is why Biden cannot return to the JCPOA regardless of Tehran’s immediate decisions.

During the Obama administration, no foreign-policy issue was more politically fraught than negotiations with Iran. Lacking any support from Republican members of Congress, Obama structured the JCPOA as a political agreement rather than as a treaty, which would have required ratification by two-thirds of the Senate. The partisan divide further deepened when Trump withdrew from the deal in May 2018, even though Iran had remained in compliance. With control of the next Senate depending on run-off elections on 5 January 2021 in the normally Republican-leaning state of Georgia (which only elected Biden by a narrow margin this November), Biden will find it difficult to win Congressional support for restoring sanctions relief for Iran without extracting additional concessions. Even some Democrats, supportive of Israel, believe that Biden should not rejoin the JCPOA without extending its timeline, or else he risks squandering the stock of leverage Trump’s sanctions have supposedly built up.

In the final weeks of Trump’s term of office, his team has sought to further restrict Biden’s room for manoeuvre by adding more sanctions on Iran in the name of non-nuclear-related concerns. On 26 October, for example, the US Treasury Department sanctioned Iran’s Ministry of Petroleum and the National Iranian Oil Company under US counter-terrorism authorities. It has been reported that, in mid-November, the Treasury will sanction several Iranian individuals and entities that were connected with the deadly repression of protesters in 2019. Sanctions on humanitarian or counter-terrorism grounds generally command wider support and thus require more political capital to unravel.

Trump’s special representative for Iran, Elliott Abrams, has declared that the purpose of the new sanctions is to bind Biden’s hands. While visiting Israel to coordinate policy in early November, Abrams said that the Trump administration wants to announce a new set of sanctions on Iran every week until 20 January. By being blatant about this scorched-earth strategy, however, the Trump administration may have antagonised some of the moderate Democrats who in 2015 were sceptical about the JCPOA.

In any case, Biden may find that the easiest course of action is to simply order the Treasury not to implement sanctions that for political reasons he cannot lift. The Biden administration is highly unlikely to apply any penalties against friendly countries that engage in trade with Iran that was allowed under the JCPOA and might say so publicly. Such a declaratory policy would be diametrically opposed to the Trump administration’s threats to penalise any entity that disregarded the snapback of all United Nations sanctions against Iran that the US unilaterally, and in opposition to all but one other Security Council member, declared on 19 September. Iran can be expected, however, to want something more concrete than a policy of non-implementation.

Political dynamics in Iran regarding the deal are even more complicated. Supreme Leader Ayatollah Sayyid Ali Khamenei, who must approve any negotiations, strongly doubts the wisdom of engaging with the US. Senior government leaders have insisted that Tehran can again abide by the nuclear limits only if Washington first honours its commitments. Since Biden cannot unilaterally return to the JCPOA either, there would need to be a step-by-step process involving simultaneous measures.

Coordinated steps

Because the architecture of the JCPOA remains intact and Iran exceeded the limits over the past 18 months in ways that were largely reversible, returning to compliance is straightforward in technical terms. Tehran would need to reduce the maximum level of uranium enrichment from the current 4.5% U-235 content to 3.67% U-235; reduce the stockpile of lowenriched uranium (LEU, which is currently 12 times the limit); disable enrichmentrelated equipment at the underground facility at Fordow; remove several hundred advanced centrifuges at the enrichment plant at Natanz; and disassemble several dozen other more advanced machines at the pilot enrichment plant at Natanz that exceed the R&D limits of the deal. Former US secretary of energy Ernest Moniz, a physicist who helped negotiate the JCPOA, estimates that these steps would take about four months.

These requirements are less complicated than the steps Iran took in the latter half of 2015 that allowed it to meet the accord limits in six months. Back then, in addition to sharply reducing its LEU stockpile and reconfiguring the Fordow facility so it could not enrich uranium, Iran had to remove 13,500 centrifuges and associated infrastructure from the main enrichment facility at Natanz, remove and disable the calandria from the Arak research reactor, and export 81 metric tonnes of heavy water (which, inter alia, is used as a neutron moderator in reactors that produce plutonium). Today, according to an 11 November report by the International Atomic Energy Agency (IAEA), Iran has just several dozen more centrifuges at the main Natanz plant than are allowed, although it plans to install several hundred more in the months ahead. The latest report also said that Iran is currently below the 130-metric-tonne limit of heavy water on hand, and is not preparing Arak to be able to produce weapons-grade plutonium.

Reducing excess LEU would be easier than in 2015. At that time, the LEU stockpile had to be cut back from 10,000 kilograms to 300 kg (in the form of uranium hexafluoride, or UF6). When Biden assumes office in January 2021, Iran’s stockpile is likely to be between 4,000 and 5,000 kg of UF6. This could be enough for three nuclear weapons if it were further enriched to weapons grade. Down-blending the enrichment level is one way to reduce the stockpile, but it would be quicker to follow the 2015 example and send the excess to Russia in exchange for natural (unenriched) uranium, although the logistical issues relating to such a swap would need to be negotiated. Coming into JCPOA compliance would also require complicated negotiations on how to address the advances Iran has made in enrichment R&D, which exceeded the terms of the deal and cannot be reversed in terms of the knowledge gained.

Although Iran has remained in compliance with most of its verification commitments under the JCPOA, one minor inspection issue will need to be resolved. Because Iran had manufactured centrifuge rotor tubes using carbon fibre that was not under continuous IAEA surveillance, the agency will need to sample the carbon fibre spools. A more difficult problem concerns IAEA requests for clarification of issues and for access to sites mentioned in Iranian nuclear archives obtained by Israeli intelligence in January 2018. Although Iran temporarily defused the issue by allowing IAEA access to two sites in August and September 2020, the agency considered Iran’s answers to its questions ‘not technically credible’, according to the latest report. IAEA environmental samples at a previously unreported location detected the presence of LEU. If this anomaly cannot be satisfactorily explained, Iran could be found to be in violation of its safeguards agreement, which requires reporting of nuclear material and activity. The discovery of nuclear activity that preceded the JCPOA would not be a violation of the accord, but it would cast a shadow on already complicated arrangements to restore the deal.

In the expectation that it would take time to negotiate the terms of both sides coming back into compliance with the JCPOA in a simultaneous manner, some Western experts have suggested a staged approach. This could start with a ‘freeze for freeze’ arrangement, similar to the November 2013 Joint Plan of Action, when both sanctions and enrichment capacity were capped and slightly rolled back. Other analysts have suggested a more robust initial set of reciprocal measures on sanctions relief and enrichment, similar to what French President Emmanuel Macron sought to broker last year. Iranian commentators, however, say that adverse political dynamics in Tehran make it unlikely that Iran will relinquish any leverage it has concerning enrichment while the bulk of sanctions remain in place.

Most Western commentators in favour of restoring the JCPOA argue, on political and pragmatic grounds, that steps to do so should be taken quickly. New US presidents are usually considered to have the most political capital to adopt difficult policies within the first six months of their term. Iran’s steadily growing nuclear programme provides another reason for urgent action. The so-called ‘break-out’ time, by which Iran could produce enough highly enriched uranium for an atomic bomb, has been reduced to as low as three and a half months, according to some experts. The JCPOA was structured to maintain the break-out time at no less than 12 months for over a decade.

A further reason to move quickly is that Iranian President Hassan Rouhani, whose government negotiated the nuclear deal, will finish his second and final term in early August 2021, following an election on 18 June. With moderates having suffered a sharp loss in popularity over the demise of the JCPOA, he is expected to be replaced by a hardliner who would demand more favourable conditions for returning to the JCPOA limits. The direction of the Iranian political pendulum was evident in the February 2020 parliamentary elections, which produced a large conservative majority. The best window of opportunity for Biden may therefore close by summer 2021.

Yet the common wisdom that Biden should move quickly may be misguided. Rouhani’s own political capital within Iran is far lower than when he made the deal in 2015, and his domestic opponents will want to deny him the laurels of ending his term by restoring it. It may not necessarily be easier for Biden to win a diplomatic victory with Rouhani than with his (presumably) conservative successor.

Iran’s reaction

Whether Iran will accept a simple ‘return for return’ offer by Biden is unclear, as leaders in Tehran continue to express deep mistrust of the US. Although many Iranian citizens cheered Trump’s defeat, the leadership professed disinterest in the outcome. Rouhani said what mattered was not who won the election but what policies they would pursue. On 7 November, Khamenei on Twitter denounced the US election as a ‘spectacle’ and a sign of the ‘definite political, civil, and moral decline of the US regime’. Four days earlier, on the day of the election, he said Iran’s policy would remain the same whoever the next president was.

Iran’s government spokesman, Ali Rabiei, explained that policy on 27 October, when he told reporters that the US must not only return to the deal but compensate Iran for economic losses it suffered after Trump withdrew from the accord and reimposed sanctions, and ‘make commitments to ensure that such violations are not repeated’. There is no provision in the JCPOA for such compensation and zero interest in Washington in providing it. Some European-based experts have suggested that European governments could seek to meet the compensation demand by arranging an economic package involving credit lines to Tehran and trade finance.

Iranian Minister of Foreign Affairs Javad Zarif has indicated a willingness to re-engage if the incoming Biden administration returns to the nuclear deal, but he ‘absolutely’ refused to renegotiate the terms of the JCPOA, including its time limits. ‘We spent more time [in 2015] negotiating those limitations than anything else’, he told a civic group in New York in September, saying it would be impossible for Iran to accept harsher terms now. ‘The JCPOA is a thing of the past and has been sealed it cannot be reopened,’ the Ministry of Foreign Affairs spokesperson added in November. Iranian leaders have also ruled out negotiating limits on the missile programme or adjusting regional policies. Yet while Zarif has insisted that ‘re-engagement does not mean renegotiation’, it seems possible that this stance could change if the US were to offer enticing concessions of its own, such as relaxing the ban on US trade with Iran.


Separate from the JCPOA, Biden can be expected to take a few unilateral steps that may somewhat improve relations with Iran. As noted above, his three-part plan includes allowing Iranian citizens to visit the US and allowing Iran to import medical supplies to combat COVID-19 without hindrance from US sanctions. He will eschew bellicose language, including Trump’s mantra of ‘maximum pressure’ and coded calls for regime change. Direct communication channels with Iran’s leadership will be restored, and Zarif will be removed from the sanctions blacklist.

While pressing Iran to respect human rights, stop missile tests and withdraw from Yemen, Biden will not pose non-nuclearrelated demands as conditions for reaching a deal on the JCPOA, as the Trump administration has done. With many Obama officials who negotiated and promoted the deal likely to populate its ranks, the Biden administration will surely follow Obama’s example of giving priority to reducing the perceived nuclear danger from Iran. But if Biden can make progress in facilitating an end to the Yemen conflict, it could ease the way for an agreement on the nuclear issue. Calming the conflict arenas in which Iran is involved would also reduce the danger of an inadvertent military clash between US and Iranian forces. This autumn, Iran reportedly prevailed upon its proxy militia in Iraq to reduce rocket attacks against US forces. Iran may judge that continuing to exercise restraint as Biden takes office is in its best interest. It would be wrong to expect real rapprochement between Washington and Tehran while Khamenei remains supreme leader. Reviving the JCPOA does, however, at least appear possible.

Iran’s centrifuges continue to spin and additional machines are coming into operation, more enriched uranium is produced, and breakout times become shorter. All these are fueling fears that time is working in the Iran’s favor. Iran is progressing towards a nuclear weapons capable state; indeed, excess enrichment capacity itself could be one such definition. But the permutations are complex and various elements enter the mix. The determination of Iran’s nuclear path encompasses technical as well as political dimensions. Rigorous safeguards are not the only ingredient but are certainly a necessity one in addressing Iran’s nuclear program.


Hurley, L. 2016. “U.S. Top Court Rules Iran Bank Must Pay 1983 Bomb Victims.” Reuters, April 20.

Varzi, C. 2016. “Iranian Top Brass Meet to Discuss Response to US Sanctions.” Al Monitor, December 7., Accessed on 1 May 2021 at 2.30 PM.