Coping with Sabotage and Seabed Security Threats in the Baltic Sea: a Regional Maritime Security Policy

The security of undersea infrastructure in the Baltic Sea is increasingly at risk due to suspected sabotage incidents targeting communication cables. These disruptions have led to significant financial losses and heightened concerns among regional states. This new HCSS guest paper by Adriana Ávila-Zúñiga-Nordfjeld proposes a cooperative regional approach to maritime security, advocating for the expansion of the Helsinki Convention and its governing body, HELCOM, to include seabed security measures.

The paper highlights that under existing international law, specifically UNCLOS, coastal states have sovereignty over their territorial waters and Exclusive Economic Zones (EEZs). However, while UNCLOS protects the right to lay and maintain submarine cables, it does not explicitly address sabotage in high seas regions. Given that the Baltic Sea consists entirely of territorial waters and EEZs of coastal states—without any high seas—it presents a unique opportunity for coordinated regional action.

Ávila-Zúñiga-Nordfjeld argues that the current international legal framework leaves gaps in addressing non-state actors conducting sabotage activities. The responsibility for investigating and penalizing such incidents largely falls on the flag state of the vessel involved, rather than the state whose infrastructure was attacked. This loophole makes it difficult to enforce security measures effectively, particularly in the context of hybrid threats, such as those allegedly linked to geopolitical tensions with Russia.

The paper recommends the creation of a regional maritime security policy under the existing Helsinki Convention framework. This would enable coastal states to enhance cooperation, standardize investigative procedures, and establish joint penalties for crimes against undersea infrastructure. Expanding HELCOM’s mandate to cover maritime security would also accelerate implementation, leveraging existing diplomatic and governance structures.

A regional agreement would ensure a unified response to threats, improve information sharing, and enhance deterrence capabilities. It would help avoid duplication of efforts, streamline maritime security operations, and reinforce Baltic nations’ resilience against emerging security challenges. While Russia is a contracting party to the Helsinki Convention, the proposal suggests that other regional states could proceed with security measures even if Russia opts out through the right of reservation.

By strengthening maritime security cooperation, Baltic states can safeguard critical infrastructure, mitigate risks, and enhance regional stability. The paper underscores the urgency of initiating negotiations to integrate security considerations into existing environmental agreements, providing a comprehensive approach to maritime governance in the Baltic.

Author: Adriana Ávila-Zúñiga-Nordfjeld, Senior Lecturer, Swedish Defence University, University PhD (Maritime Administration: Law, Policy, Defence and Security).

This HCSS paper is part of a series of guest contributions following the NATO Seminar on Seabed Security, organised by TNO and HCSS, in close cooperation with the Dutch Ministries of Defence and Infrastructure & Water Management, on March 27, 2025.

Edited by HCSS deputy director Michel Rademaker. The Seminar on Seabed Security was part of a series of NATO Summit pre-events organised by HCSS together with other partners to set the stage for the 2025 NATO summit in The Hague, on June 24 and 25.