Tehran and Moscow: Alignment and Divergence in the Caspian June 9, 2021 Share The complexities, converging interests, and persistent tensions marking Iranian-Russian relationships are evident in their policies toward the Caspian Sea region. Iran and Russia are the two largest countries that border the sea, the world's largest inland body of water. The Caspian region therefore provides many opportunities for diplomatic, economic, and military engagement between Iran and Russia. Some issues of mutual importance relating to the Caspian include the Nagorno-Karabakh War, the Afghanistan and Iraq conflicts, NATO partnerships in the Caucasus region, and the construction of trans-Caspian pipelines. Iran and Russia doggedly pursue their own goals in the region, which align in some areas but not others. For example, policy makers in both countries do not want the other Caspian states to realize their goals of diversifying their trade routes and markets, which would decrease their reliance on Iranian and Russian oil and gas. Furthermore, Tehran and Moscow share the goal of keeping Western militaries out of the Caspian Sea region. Even when their goals align, Iran and Russia still pursue independent policy lines. Tehran and Moscow can also collaborate for short-term tactical advantage, such as to secure mutual gains at the expense of third parties, even when their long-term objectives may differ. For instance, while offering Tehran some support in its conflict with the West, Russia exploits Iran’s isolation from possible Western partners for economic and security leverage.