Written by Sebastian Clapp.
Russia’s escalating hybrid attacks, including drone incursions, have prompted NATO’s Operation Eastern Sentry and the European Union’s (EU) plans for a European Drone Wall and Eastern Flank Watch. These initiatives aim to strengthen eastern defences but face disputes over cost, feasibility and strategic focus. Members of the European Parliament (MEPs) have welcomed the initiatives.
Eastern Shield and Baltic Defence Line
Estonia, Latvia and Lithuania are jointly developing the Baltic Defence Line, a fortified line along their borders with Russia and Belarus to delay and disrupt incursions while enabling NATO reinforcements to deploy. Poland is also building an East Shield, a defence infrastructure project along its borders with Belarus and Russia to enhance NATO and EU security through surveillance, mobility infrastructure and physical barriers. The Baltic States and Poland aim to coordinate these efforts to secure EU funding and jointly procure equipment under SAFE, improving efficiency and interoperabilit
In the past few months, there has been a marked escalation of Russian hybrid warfare directed against EU and NATO member states, prompting alarm among European leaders and citizens. Moscow has also resorted to conventional military measures, including incursions by manned fighter aircraft into Estonian airspace and drones in Polish and Romanian airspace. Furthermore, at least 10 European countries (Belgium, Lithuania, Latvia, Denmark, Norway, Romania, Poland, Estonia, Germany and France) have reported drone sightings over airports and military installations, with officials suggesting in some cases that the drones may have been launched from vessels operating offshore. The French military authorities detained two persons aboard a Russia-linked oil tanker suspected of launching drones. Although many of the devices recovered so far were unarmed and some merely decoys, European governments regard these intrusions as a form of hybrid threat designed to test air-defence readiness and impose psychological and economic costs. Several statements by European leaders noted that they assume Russian responsibility. Following the drone incursions, Poland invoked Article 4 of the Washington Treaty, triggering urgent NATO consultations just days after Estonia had done the same. In response, NATO launched Operation Eastern Sentry. Its primary objective is to strengthen NATO’s capabilities in the air, at sea and on land to counter military threats from Russia, with a particular focus on intercepting Russian drones violating the airspace of NATO member states. Eastern Sentry introduced a collective framework and operational approach to air defence along NATO’s eastern flank. The incidents have also hardened national positions. Six European NATO allies have declared that they will use force to defend their airspace, with Lithuania authorising peacetime drone shoot-downs. According to an IISS expert, NATO now faces the challenge of mounting a cost-effective defence. Deploying fighter jets and expensive air-to-air missiles to counter drones is operationally possible but fiscally unsustainable.
Eastern Flank Watch and European Drone Defence InitiativeCommission President von der Leyen first called for the establishment of an ‘Eastern Flank Watch’ during her 2025 State of the Union address. The defence readiness roadmap 2030 scoping paper, which was circulated to Heads of State and Government prior to the informal European Council in Copenhagen, underlines that ‘In light of the continued military aggression against Ukraine, and the recent increase of violations of air space of Member States, two flagship projects – The European Drone Wall and The Eastern Flank Watch – require special urgency and should be moved forward expediently.’ According to media reports, the initiative has split EU capitals: frontline states such as Poland, the Baltic States and Finland see it as an urgent necessity, while countries further from Russia’s borders, including France, Germany, Italy and Greece, question its cost, technical feasibility and the risk of Brussels encroaching on national defence prerogatives. Although EU leaders in Copenhagen ultimately endorsed the plan in principle – the main results of the informal European Council note that leaders broadly supported priority flagships presented by the Commission and the High Representative, including the European Drone Wall and the Eastern Flank Watch – significant divisions remain over funding, scope and branding. Sceptics warn it will not address broader vulnerabilities such as cyberattacks, ammunition shortages or command structures.
In October 2025, the Commission and the High Representative put forward the European defence readiness roadmap 2030. It proposes a series of European Readiness Flagships to strengthen the EU’s collective defence through coordinated investment in critical capability areas. These initiatives – the (now renamed) European Drone Defence Initiative,the Eastern Flank Watch, the European Air Shield and the European Space Shield – aim to reinforce Europe’s resilience against emerging military and hybrid threats while enhancing strategic autonomy and operational readiness. Open to all Member States, the flagships are cross-sectoral, covering defence, border management, internal security and the protection of critical infrastructure. Member States would lead the initiatives, determining objectives, governance and funding allocations; the Commission would facilitate coordination, offer technical assistance and ensure coherence across EU instruments and funding mechanisms; and the High Representative would ensure alignment with agreed EU capability priorities and coherence with NATO defence plans. Coordination frameworks should be agreed upon by spring 2026. According to the roadmap, the EU Military Staff will conduct a classified annual assessment of Member States’ capabilities and shortfalls – aligned with NATO’s targets and Ukraine’s needs – to inform procurement priorities and underpin an annual defence readiness report to the European Council each October, tracking collective progress across key capability areas.
The European Drone Defence Initiative aims to develop a cutting-edge interoperable system for countering and deploying drones. It will establish a multi-layered network capable of detecting, tracking and neutralising hostile drones, while also enabling precision-strike capabilities through advanced drone platforms. Drawing extensively on Ukraine’s battlefield experience, it will be closely connected to the proposed Drone Alliance with Ukraine (President von der Leyen announced during her State of the Union address that Europe will allocate €6 billion from the interest generated on immobilised Russian assets to support Ukraine’s drone production). Its dual-use dimension would allow applications in civilian contexts such as border protection and disaster response. It is expected to be launched in Q1 2026, reach initial operational capacity by the end of 2026 and be fully functional by the end of 2027.
The Eastern Flank Watch would reinforce the EU’s eastern borders against hybrid, cyber, maritime and conventional threats from Russia and Belarus through the integration of air defence, electronic warfare, surveillance and maritime security systems. It will combine anti-drone and air-defence capabilities with improved ground and naval assets, supporting situational awareness and rapid response capacity, coordinated closely with NATO’s integrated command and control structures and operations, such as Baltic Air Policing and Operation Eastern Sentry. This will enhance deterrence, strengthen interoperability and secure the EU’s land and sea frontiers. Implementation is to begin in 2026, with initial operational capabilities expected by late 2026 and full functionality achieved by the end of 2028.
The European Council is expected to endorse the two flagship projects by the end of 2025. An expert contends that the Drone Wall does not constitute a strategic response to Russian hybrid warfare, as it fails to counter it directly. Instead of investing in largely symbolic defences, states should focus on deterrence by enhancing Ukraine’s long-range strike capabilities. The main purpose of the Drone Wall is to reassure worried populations. Another analyst argues that the Drone Wall paradigm is ‘promising’ as a start, provided it is institutionalised, properly coordinated and legal frameworks are adjusted.
European Parliament positionMEPs condemn Russia’s violations of airspace and drone incursions targeting EU and NATO members as part of Moscow’s hybrid warfare. They welcome initiatives such as the EU Drone Wall and Eastern Flank Watch, while emphasising the importance of providing full protection for all Member States facing direct security threats, including those along the EU’s southern flank. They also call for deeper defence cooperation with Ukraine, particularly on drone technology and countermeasures, using instruments like the European defence industry programme (EDIP) and the Security Action for Europe (SAFE) instrument.
Read this ‘at a glance note’ on ‘Eastern Flank Watch and European Drone Wall‘ in the Think Tank pages of the European Parliament.