US-Iran nuclear talks will shape not only Iran’s nuclear future but also the integrity of global nonproliferation norms and the broader energy security environment.
After years of stalled diplomacy, US and Iranian officials are once again at the negotiating table. The newest round of US-Iran nuclear talks comes amid altered geopolitical conditions—and with far higher stakes for global nonproliferation.
Unlike the Biden-era negotiations that dragged on without results, the Trump administration, similar to the rest of its agenda, is looking to move swiftly on a deal. Early on in the negotiations, Iran’s Foreign Affairs Ministry described the talks as “constructive” and “respectful.” But progress seems to be stalling, particularly over Iran’s enrichment program.
Fundamental issues remain unresolved: Iran continues to enrich uranium beyond the limits set in the 2015 Joint Comprehensive Plan of Action (JCPOA), and distrust between the US and Iran persists. From a nonproliferation standpoint, this is not just a question of diplomacy—it’s a test of whether global nuclear nonproliferation norms can hold strong in the face of mounting pressure.
A Weakened Iran
Much has changed since 2015, when the JCPOA was signed. Iran is in a much more vulnerable position. The collapse of the Assad regime in Syria and the attacks on its key regional proxies—Hamas, Hezbollah, and the Houthis— have eroded Iran’s regional influence. While Tehran has pledged to rebuild Hezbollah, they are constrained by international sanctions, a collapsing economy, and domestic unrest. This has left the regime struggling at home.
At the same time, Russia, a once crucial military partner, has grown increasingly distant. The fall of the Assad regime ended the joint military effort that was established in 2015, dissolving one of the few areas of overlapping interest. Meanwhile, the revival of Trump’s maximum pressure strategy and US engagement with Gulf states has put Russia in a position where maintaining ties with Iran could jeopardize its relations with other countries in the region. Finally, with fighting intensifying in Ukraine, a ceasefire deal nowhere in sight, and Moscow becoming less dependent on Iranian military support, Tehran has become far more expendable in Russia’s geopolitical calculus.
Within the new regional reality, Iran is also increasingly reliant on a narrowing set of economic partners. After the reintroduction of sanctions on Iran’s oil exports, the majority of Iran’s oil now flows to China, which has long been Iran’s largest trading partner. For Tehran, maintaining close ties with China is critical, as it “offers investment, technology, and a reliable market for its energy exports.” In recent weeks, Tehran has doubled down on its relationship with China as well as Russia, despite the current complications in the relationship. Ahead of the second round of US-Iran nuclear talks, Iranian Foreign Minister Abbas Araghchi met with Russian officials, and prior to the third round, he briefed Chinese counterparts in Beijing. Despite these efforts, there appear to be clear limits to these relationships. While Iranian President Masoud Pezeshkian and Russian President Vladimir Putin recently signed a 20-year strategic partnership, the provisions are not new and echo earlier treaties.
Notably, both Russia and China were signatories to the 2015 US-Iran nuclear deal, and their positioning could influence the trajectory of any new agreement. While both Russia and China support diplomacy with Iran, it is clear that their own strategic and economic interests will take precedence and cannot be threatened by the relationship. With Tehran’s domestic and regional vulnerability, as well as its increased dependence on these fair-weather friendships, it lacks the geopolitical leverage needed to secure a new nuclear deal on favorable terms.
Trump’s Maximum Pressure Strategy
Donald Trump has reinstated his “maximum pressure” campaign and made his position clear: he will not accept a nuclear-armed Iran. On top of denying Iran a nuclear weapon, the strategy outlines broader objectives which include preventing Iran from developing intercontinental ballistic missiles, dismantling its terrorist proxy networks, and countering its advancement of conventional and asymmetric weapons systems. In line with this strategy, the US Treasury has expanded sanctions on Iran’s nuclear entities and oil exports.
In a March letter to Iran’s Supreme Leader Ali Khamenei, President Trump emphasized a two-month deadline for reaching a new US-Iran nuclear deal. Reflecting the administration’s more assertive negotiation style, Steve Witkoff, US Special Envoy to the Middle East, stated, “A deal with Iran will only be completed if it is a Trump deal.” However, that deadline has now passed.
Iran’s Nuclear Program
Iran’s nuclear program today is significantly more advanced than it was in 2015. The International Atomic Energy Agency (IAEA) has confirmed that Iran is enriching uranium to 60 percent—just a short step away from the weapons-grade threshold of 90 percent. Additionally, its total stockpile has grown to over 9,247.6 kilograms, a significant increase from the IAEA’s February report.
According to a March report from the IAEA, “Iran remains the only non-nuclear weapon state enriching uranium to this level, raising significant concerns over potential weapons development,” and IAEA Director General Rafael Mariano Grossi has noted that Iran could make several nuclear weapons with its current stockpile of enriched uranium. Under the JCPOA, Iran was allowed to enrich uranium to 3.67 percent purity—the level necessary for nuclear energy programs—and keep a stockpile of 300 kilograms. It also faced limits on the types of centrifuges it could operate, curbing its capacity to pursue a nuclear weapon rapidly.
The technical reality makes the situation more urgent. Experts note that enriching uranium to 20 percent constitutes roughly 90 percent of the effort required to reach weapons-grade levels. Once a country passes this threshold, the jump to a bomb becomes much shorter. Today, the Institute for Science and International Security assesses Iran’s breakout time—the period required to produce a nuclear weapon—at zero.
This presents a challenge for negotiators. While Iran has maintained that its program is only for civilian energy use, enrichment levels and Iran’s continued restrictions on international inspectors raise doubts. Addressing this impasse requires more than political maneuvering. In 2015, the JCPOA’s durability stemmed in part from expert-level dialogue between scientists, including US Energy Secretary Ernest Moniz and Ali Akbar Salehi, then-head of the Atomic Energy Organization of Iran. Reestablishing that kind of technical cooperation is essential to crafting a framework that can both verify compliance and contain Iran’s nuclear ambitions.
The Fight for Enrichment
At the very end of May, the United States put forth a proposal. It would allow Iran to maintain a low level of enrichment for a period of time, but would prohibit the construction of any new enrichment facilities. The proposal also demands the dismantling of critical infrastructure for conversion and processing, halts new research and development (R&D) on centrifuges, and would reduce Iran’s enrichment to three percent. Additionally, underground enrichment facilities would have to become non-operational for some time, and a system of monitoring and verification would be established, including approval of the IAEA’s additional protocol.
Iran, in response, has criticized the proposal for not including elements that reflect the negotiations thus far, that the proposal fails to include the lifting of sanctions, and that enrichment is a “non-negotiable.” Supreme Leader Khamenei has been particularly vocal about the proposal, saying, “Uranium enrichment is the key to our nuclear programme” and that “The rude and arrogant leaders of America repeatedly demand that we should not have a nuclear programme.” A counterproposal from Iran is expected shortly and will likely deal with uranium enrichment and steps to lift US sanctions. Put very simply by Foreign Minister Abbas Araghchi: “No enrichment, no deal. No nuclear weapons, we have a deal.”
The Stakes for Global Nonproliferation
These talks are a test of the international nonproliferation regime. While the war in Gaza has remained relatively contained, the Middle East still remains a volatile region. In 2022, Saudi Arabia indicated it would pursue nuclear weapons if Iran did—raising the risk of a regional arms race—and potentially prompting a scenario in which Israel is forced to formally acknowledge its own nuclear capabilities. The fall of nuclear restraint in the Middle East would not only undermine decades of nonproliferation work—it could collapse the global norm that separates civilian nuclear energy from military capability.
Tensions have already escalated. Prior to US-Iran nuclear talks in Oman, President Trump warned that Israel would take the lead in any military strike against Iran if Iran fails to abandon its nuclear weapons program. Meanwhile, IAEA Director General Grossi has reiterated his call for Tehran to fully cooperate with the IAEA’s investigation into the finding of uranium at undeclared nuclear sites, which Iran has claimed is biased and built upon unreliable information.
It has also become clear that a return to the original JCPOA is no longer viable. Iran has breached core elements of the agreement since the US withdrawal in 2018, including uranium enrichment limits, centrifuge restrictions, and stockpile caps. No agreement today can undo what Iranian scientists have learned in the intervening years.
Yet, a new deal remains necessary should nonproliferation remain the global norm. However, it must go further than the first agreement. Trump’s withdrawal from the JCPOA was rooted in its failure to address Iran’s ballistic missile program and its destabilizing regional behavior. These issues will need to be addressed directly in any new agreement.
A successful agreement should be built on technical constraints, robust verification mechanisms, and broad multilateral support. The original JCPOA was not just a US–Iran agreement—it was brokered with the other members of the United Nations Security Council, including China, Russia, the United Kingdom, and France, along with Germany and the European Union. Their involvement lent legitimacy, accountability, and technical expertise.
The support of a broad coalition, one that has been deeply involved in nuclear nonproliferation efforts throughout the years, should be central in negotiations. Even though Iran is in a more vulnerable position and the Trump administration has more leverage than in past US-Iran nuclear talks, international coordination is still essential. Some US allies, such as Israel and Saudi Arabia, felt excluded from the JCPOA and are still wary of diplomacy. At the same time, Trump’s confrontational approach, through tariffs and provocative rhetoric, with long-term allies, has strained relationships. In the interest of global security and nonproliferation, the United States must gather the trust of key partners.
Ultimately, a US-Iran nuclear deal that stops Iran’s pursuit of nuclear weapons and creates monitoring and verification of Iran’s civilian nuclear energy program is part of a much broader goal of reaffirming the institutions and standards that make proliferation harder everywhere. That will require cooperation, pressure, and diplomacy grounded in realism.
About the Author: Emily Day
Emily Day is an experienced researcher, writer, and editor with expertise in geopolitics, nuclear energy, and global security. She is an Associate Editor of Energy World at the National Interest, a Della Ratta Energy and Global Security Fellow at the Partnership for Global Security, and a Research Associate at Longview Global Advisors, where she provides insights on global political and economic trends with a specialization in utilities, risk, sustainability, and technology.
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