Black Sea Security as the White Knight for peace?

The Black Sea region is a mosaic of political systems, security alignments and strategic priorities, where Russia’s war against Ukraine has diversely affected the commercial and military standing of littoral states, namely – in addition to Russia and Ukraine – Romania, Bulgaria, Türkiye and Georgia. This report explores how Russia’s war on Ukraine affects Black Sea security and Europe’s capacity to enhance regional deterrence.

For Ukraine, the Black Sea remains a vital economic lifeline, particularly in supporting the country’s agricultural exports. For Russia, the region represents a strategic and economic hub for projecting power and hindering others to benefit from the Black Sea. Ukraine prioritises restoring its sovereignty and obtaining lasting security guarantees on land, in the air, and at sea, while Russia seeks to entrench territorial control and influence. As a result, their positions remain too far apart for meaningful negotiations. Reaching an agreement on the governance of the Black Sea is considered essential not only for a future settlement of the war, but also for Europe’s broader security architecture, including food and energy security, maritime safety, and regional stability. At the same time, emerging trade corridors that bypass Russia, along with the region’s renewable and offshore energy potential and growing infrastructure investments, give the Black Sea renewed geostrategic significance for the European Union.

Consequently, for Russia, maintaining or even intensifying hybrid operations in the region – ranging from disinformation and military build-up to the covert sabotage of undersea infrastructure, gas platforms and commercial traffic – remains a viable strategy. Countering these threats and harnessing the region’s strategic value depend on securing Ukraine’s access to the Black Sea, reducing the vulnerabilities of littoral states, and strengthening deterrence through a dedicated maritime coordination mechanism.

Constructive engagement among the Black Sea littoral states, Türkiye and Ukraine among them, and the EU constitutes a key dimension of regional security efforts. Ankara’s control of the Turkish Straits under the Montreux Convention provides it with influence over any ceasefire mission. Such a mission would necessarily involve a visible maritime force, real-time intelligence sharing, and direct coordination with all littoral states. The EU’s emerging approach appears to build on the Mine Countermeasures Black Sea Task Group and the EU Maritime Security Hub, in addition to creating new structures, it aims to develop a more permanent security architecture supported by credible deterrence and sustained military and technological assistance to Ukraine — including guaranteed access to its ports and modern air-defence and naval systems.

Regional stability also depends on the economic and political resilience of the littoral states. Improving connectivity can strengthen their resilience and ability to contribute to a stable and secure Black Sea region. EU member states, Romania and Bulgaria, serve as important anchors of regional resilience, yet further upgrades to transport links with Türkiye and Moldova are needed to enhance military mobility and stimulate economic growth. A broader Black Sea strategy should therefore be closely integrated with the EU’s other North–South connectivity initiatives — particularly the Baltic–Black Sea–Aegean and Corridor 8, which links the Black Sea with Adriatic Sea routes — as well as the Global Gateway, ensuring that investments advance both economic and defence objectives. Europe can reinforce stability in the Black Sea region by strengthening credible maritime deterrence, integrating monitoring efforts, and sustaining economic engagement.

Authors:

Julia Soldatiuk-Westerveld - Senior Research Fellow at the Clingendael Institute

Ben Bekkering - Senior Associate Fellow at the Clingendael Institute

Emma Caals - Junior Research Fellow at the Clingendael Institute

Giulio Damiani - Research Assistant at the Clingendael Institute.