Abstract In the article, we explore the factors which brought about the transatlantic coordination of the policy of imposing sanctions on Iran. We will mainly focus on the events in the 21st century when the new incentives for cooperation appeared due to the growing concern over the development of Iran’s nuclear programme. Considering the capabilities of using the tools of economic statecraft and diplomacy, we claim that the EU-US cooperation can be termed a co-leadership. The assessment and the reasons for the transatlantic break-up on this matter during the presidency of Donald Trump was examined using the concept of relative gains. We evaluate to what extent the initial goals were achieved in practice, and we also try to predict the possible consequences of the US withdrawal from the Joint Comprehensive Plan of Action (JCPOA). As to whether the effectiveness of the sanctions through the cooperation has been enhanced, the answer is ambivalent. On the one hand, the cooperating transatlantic partners managed to coerce Iran through isolating the country from international economic contacts and negotiated the JCPOA. On the other hand, Trump’s renouncement of this agreement brought many negative consequences and undermined the earlier joint effort.

中文翻译：

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合作为何成功或失败？欧盟对伊朗制裁政策案

摘要在本文中，我们探讨了导致对伊朗实施制裁政策进行跨大西洋协调的因素。我们将主要关注21世纪的事件，当时由于对伊朗核计划发展的日益关注，出现了新的合作激励措施。考虑到使用经济治国手段和外交手段的能力，我们认为可以将欧盟与美国的合作称为共同领导。在唐纳德·特朗普（Donald Trump）担任总统期间，对这一问题的评估和跨大西洋分歧的原因已使用相对收益的概念进行了研究。我们评估了在实践中实现初始目标的程度，并且我们还尝试预测美国退出联合全面行动计划（JCPOA）可能带来的后果。关于通过合作加强制裁的效力，答案是模棱两可的。一方面，合作的跨大西洋伙伴设法通过将伊朗与国际经济联系隔离开来来迫使伊朗，并通过谈判达成了JCPOA。另一方面，特朗普对这项协议的放弃带来了许多负面影响，并破坏了先前的共同努力。