The strategic partnership between Russia and Iran has been deepening since 2022 in ways that have direct implications for the Persian Gulf security environment. The relationship is not an alliance in the formal sense — no mutual defense treaty binds Moscow and Tehran, and the two countries have a long history of friction and competing interests that did not disappear when their shared confrontation with the West provided new incentives for cooperation. What has emerged is something more specific: a bilateral relationship structured around shared sanctions exposure, complementary military needs, and converging interests in reducing American influence in the regions that matter to each of them.