The Black Sea has become a flashpoint for drone warfare, with recent attacks on commercial shipping near Romania and Bulgaria exposing the fragility of Europe's maritime defences. On Tuesday, a merchant vessel sank roughly 130 kilometres off Bulgaria's coast, and another was damaged. Bulgarian Prime Minister Rumen Radev called the incident "absolutely unacceptable," though he stopped short of assigning blame while an investigation continues.
A day earlier, a Turkish-owned cargo ship carrying Ukrainian grain caught fire and sank off Romania, killing two crew members. Ukrainian President Volodymyr Zelenskyy said the vessel was struck by Russian drones. Romanian Foreign Minister Oana-Silvia Țoiu described the attack as "a flagrant violation of international law," and European Commission President Ursula von der Leyen condemned both incidents, saying, "The situation in the Black Sea is increasingly concerning. Attacks on civilian shipping are unacceptable."
These events have renewed scrutiny of the European Union's ability to safeguard one of its most vulnerable maritime corridors. In May 2025, the bloc unveiled its Black Sea Security Strategy, a framework designed to counter hybrid threats, protect critical infrastructure, and bolster regional cooperation. EU foreign policy chief Kaja Kallas warned at the time that the region was bearing the spillover effects of Russia's full-scale invasion of Ukraine, noting that "recurring airspace violations and attacks on ports and shipping lanes highlight this reality."
The strategy promised the creation of a Black Sea Maritime Security Hub, to be based in Romania's Constanța and Bulgaria's Varna, aimed at coordinating coast-guard cooperation, analysing seabed sensor data, and alerting allies to incoming threats. Yet, more than a year on, the hub remains in its conceptual phase, and the recent attacks suggest that paper commitments have not translated into operational readiness.
Capabilities lag behind strategy
European Commission spokesperson Christian Wigand defended the policy, noting that 65 projects worth €200 million have been initiated in the region. He added that the European Maritime Safety Agency has offered support to Romanian and Bulgarian authorities, including satellite imagery to enhance situational awareness. However, a leaked copy of the EU's Annual Defence Readiness report paints a bleaker picture. Prepared by the European Defence Agency with input from the Commission and the European External Action Service, the document assesses whether the 27 member states can achieve defence readiness by 2030. It identifies "critical gaps" in naval munitions, missile stockpiles, integrated air and missile defence, long-range strike capabilities, and the protection of seabed infrastructure.
Mihai Sebastian Chihaia, a maritime security expert at the European Policy Centre, argues that strategies alone are insufficient. "We have quite a few strategies, we have quite a few directions, but to really secure the Black Sea, you actually need capabilities," he told Euronews. He pointed to the need for intelligence-gathering assets such as sensors and radars, and suggested that NATO could develop a dedicated Black Sea strategy to complement EU efforts.
Romania, Bulgaria, and Turkey have stressed that they are coordinating their security efforts in the region, but Chihaia says a broader approach is still missing. The EU's defence readiness report recommends three priorities: improving maritime domain awareness, balancing investment in large combat platforms with naval strike capabilities, and investing in enablers like seabed protection. Whether these recommendations translate into concrete action remains to be seen, especially as the bloc's defence budgets face competing demands.
The human cost of the current gaps was evident this week, as rescue teams pulled injured sailors from the sea. The attacks also disrupted grain exports, a key economic lifeline for Ukraine and a source of global food security. As the EU and NATO deliberate on next steps, the Black Sea's waters remain a testing ground for the limits of European defence cooperation.
