Joint Communication to Strengthen the Security and Resilience of Submarine Cables

On February 21, 2025, the Commission and the HRVP presented the Joint Communication to strengthen the security and resilience of submarine cables. It introduces a range of measures to bolster the resilience of this critical infrastructure, addressing prevention, detection, response, recovery, and deterrence.

Communication cables connect several Member States to one another, link islands to the EU mainland, and connect the EU to the rest of the world, carrying 99% of intercontinental internet traffic. Subsea electricity cables facilitate the integration of Member States' electricity markets, strengthen their security of supply, and deliver offshore renewable energy to the mainland.

However, in recent weeks and months, incidents involving submarine cables have risked causing severe disruptions to essential functions and services in the EU, impacting the daily lives of EU citizens. This initiative responds directly to these threats.

The EU must first prevent disruptive incidents and increase its resilience against the threats and vulnerabilities of submarine cable infrastructure. It must also enhance its detection capacity to identify and anticipate threats as early as possible. Additionally, the EU must develop the necessary capacities to recover from any incident as quickly as possible. Furthermore, the EU must strengthen its deterrence posture and take action to protect the security of critical maritime infrastructure.

The key measures outlined in the Joint Communication include:

• Prevention: Strengthening security requirements and conducting risk assessments on submarine cables while prioritizing funding for the deployment of new and smart cables to increase redundancies and enhance resilience.
• Detection: Enhancing threat-monitoring capabilities in specific sea basins, such as the Mediterranean and the Baltic Seas, to build a comprehensive situational picture. This will enable earlier alerts and more effective responses.
• Response and Recovery: Improving the efficiency of the EU-level crisis framework to ensure swift action on incidents affecting submarine cables and increasing repair capacity to facilitate the rapid restoration of damaged cables.
• Deterrence: Enforcing sanctions and diplomatic measures against hostile actors and the "shadow fleet," making full use of the Hybrid Toolbox to counter hybrid campaigns. This also includes fostering "cable diplomacy" with global partners.

These strategic actions complement ongoing work by the Submarine Cable Infrastructure Expert Group, composed of Member States and the EU Agency for Cybersecurity (ENISA). They are also aligned with NATO’s existing activities and support national and regional initiatives, reaffirming Europe’s commitment to protecting critical submarine infrastructure, which is essential for global communications and energy security.

By the end of 2025, the following are expected to be presented:

• A mapping of existing and planned submarine cable infrastructure.
• A Coordinated Risk Assessment of submarine cables.
• A Cable Security Toolbox outlining mitigation measures.
• A priority list of Cable Projects of European Interest.

The security and resilience of submarine cable infrastructure were addressed in a 2024 Recommendation on the security and resilience of submarine cable infrastructure, as well as in a White Paper on "How to Master Europe's Digital Infrastructure Needs."

The EU is actively working on multiple fronts to promote cyber resilience and protect its citizens and businesses from cyber threats in an increasingly digital and interconnected Europe. The Commission is also continuing work on implementing the upgraded legal framework for the resilience of critical infrastructure, both physical and cyber, through the Critical Entities Resilience (CER) Directive and the Network and Information Systems (NIS2) Directive.

The Joint Communication of the Commission from February 21, 2025, is available in application: