The differences that existed between Mohammad Reza Pahlavi and Ali Amini, prime minister between May 1961 and July 1962, over questions of domestic policy have been well analyzed (see e.g. Willcocks, 2016 and Ansari, 2001), however the study of French diplomatic documents as well as of a variety of other primary sources in Persian shows that the issue of Iran's regional integration also played a role in the power struggle between the monarch and his energetic premier. The overthrow of the Iraqi monarchy in July 1958, seemed to make the future of Mohammad Reza Shah's regime uncertain but also led to a regional surge in state building as well as an increased interest in international institutions and regional cooperation in the context of the Cold War (Schayegh, 2013). The future of the Iranian monarchy came to be seen as even more uncertain as a major crisis developped inside Iran in the early 1960s, during which the shah’s power was temporarily curtailed. This allowed Ali Amini to act more independently than previous prime ministers. When Ali Amini publicly announced his political program in May 1961, he unambiguously stated that his external policy would be framed by abiding by the UN charter and international treaties as well as by the pursuit of good relations with all neighbouring countries (Amini, 2009). This approach to a regional policy stood in stark contrast to the shah's vision, in which Iran was meant to be the most important western-aligned power in the region while emphasizing its own presumably Aryan and even Western heritage as opposed to any ties that might link it to the Middle East (Zia-Ebrahimi, 2011, Alvandi 2014). Furthermore, French sources reveal that Amini believed that the establishment of a Middle Eastern common market, modelled on the European Economic Community, into which Iran was to be integrated, would be a crucial step for stabilising the Middle East. Amini even implied that this institution should later evolve into a federation of Arab states, which suggests that he was less concerned with any potential threat to Iran from pan-Arabism than other Iranian policy-makers at the time, including most notably the Iranian monarch (Reisinezhad, 2018). By exploring this hitherto unstudied point of contention between Prime Minister Ali Amini and Mohammad Reza Shah, this paper aims at enriching our understanding of the complex question of how Iranians conceived of their country’s spatial and regional affiliations during the twentieth century.