The three European parties to the 2015 Iran nuclear deal – France, Germany and the UK (known as the E3) – announced yesterday that they were triggering the agreement’s dispute resolution mechanism. In a joint statement, the E3 insisted that the move was undertaken “in good faith” and was aimed at salvaging the accord in response to Iranian breaches, not expediting its collapse. But resorting to the mechanism could set in motion the deal’s demise, unless Europe engages both Tehran and Washington.

First, some context. The Trump administration abandoned the nuclear deal, or Joint Comprehensive Plan of Action (JCPOA) to give it its official name, in 2018. It put in place biting sanctions against Iran. This unilateral move upended the multilateral bargain at the deal’s core, under which Iran restricted its nuclear programme and allowed rigorous international monitoring of its facilities in return for economic normalisation. With the deal’s remaining parties (France, Germany, the UK and the EU, along with Russia and China) failing to provide economic respite, Iran incrementally broke the deal’s restrictions, arguing that fewer financial dividends merit lessened compliance, a logic dismissed by the Europeans. While Tehran has ostensibly ceased observing key nuclear limits, it has not yet followed through with steps that would set off alarm bells, such as ramping up uranium enrichment to 20% or limiting the access of international inspectors.

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The dispute resolution mechanism was devised to tackle technical breaches of the deal, not a political crisis prompted by US abrogation of the agreement. It is hard to see how this process has a better chance of resolving the parties’ mutual grievances than the political talks that preceded it. Resorting to the mechanism, which is an option the Europeans have been debating for months, is therefore a statement of concern over Iran’s violations and also a gambit for bringing Iran back into full JCPOA compliance. The dispute resolution process could, in theory, ratchet up the urgency in talks with the Iranians, holding out the possibility of reinstating UN sanctions against Iran – which the JCPOA lifted – should the efforts come to naught.

But if that is the plan, it also carries risks. For one thing, while the Europeans underscored in their announcement that they had “worked tirelessly to support legitimate trade with Iran”, that labour has not translated into practical dividends for Iran. Nearly a year after they instigated the Instex mechanism that sidesteps US sanctions, which was designed to facilitate trade with Iran without exposure to US sanctions, the initial transactions are yet to be finalised. Seen from Tehran, Europe is still asking Iran to deliver fully on its JCPOA commitments while delivering little in return.

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Furthermore, the decision could tip the debate in Tehran away from what Europe is hoping for: internally, hardliners have argued at each stage of Iran’s carefully staggered breaches for more provocative steps to jolt the deal’s remaining signatories into taking meaningful steps towards upholding their end of the bargain. The Iranians have also indicated that the return of UN sanctions would lead them not just to abandon the JCPOA but to withdraw from the nuclear nonproliferation treaty (NPT) – a step that would likely push Iran further into the diplomatic cold but also place an obstacle in front of future talks.

Still, with the dispute resolution process now under way, Europe should work three tracks in parallel. With the Iranians, the Europeans should underscore a key point in their joint statement: that their resort to the mechanism is a means for intensified diplomacy. If Iran refrains from further breaches to the agreement, the process, which theoretically could lead to UN sanctions within 65 days, can be extended. Among themselves, France, Germany and the UK can step up efforts to put INSTEX into effect, and additional means of boosting trade with Iran, which probably requires a certain degree of American acquiescence and European willingness to stand up to U. pressure.

While Washington will likely seize on the dispute resolution decision to pressure the Europeans into further isolating Tehran, the Europeans can instead make the point to the Americans that nearly two years of coercive policies have neither curbed Iran’s regional influence nor yielded a “better” nuclear deal.

In short, by triggering the resolution mechanism the E3 countries could be embarking on a path that accelerates the crisis they are seeking to prevent. At this point, their priority should be to extend the timeframe provided by the mechanism to seek to convince Iran to resume compliance with the JCPOA in exchange for meaningful economic reprieve. Ultimately, none of the JCPOA’s signatories are fully satisfied with the existing agreement. But building on it, rather than watching it collapse, should be the way forward.

• Ali Vaez directs the Iran Project at the International Crisis Group