European authorities are investigating what officials describe as “highly likely” acts of sabotage against energy and communications infrastructure on the Baltic seabed, with suspicion inevitably falling on Moscow.
The fragile web of undersea cables and pipelines crisscrossing the Baltic Sea is once again under threat.
Reports from Swedish and Finnish maritime agencies, corroborated by NATO monitoring data, suggest a coordinated operation targeting multiple assets. At least two telecommunications cables and a secondary gas pipeline—running between Sweden and Lithuania—suffered “unusual” pressure loss and connectivity disruption earlier this month. Preliminary investigations point toward intentional damage, most likely by submersibles or remotely operated vehicles.
This is not the first time the depths of the Baltic have become a theatre for shadow conflict. The September 2022 explosions that crippled the Nord Stream pipelines—widely attributed to Russian operatives though never conclusively proven—remain a chilling precedent. Today’s developments suggest that the Kremlin may be continuing to employ undersea sabotage as a form of hybrid warfare, designed to unsettle Europe without provoking an open military response.
A Calculated Message
The incidents coincide with a sharp deterioration in East-West relations. As the war in Ukraine grinds into its fourth year, and with Russia now deeply entrenched in Donbas and Kharkiv oblasts, the Kremlin has increasingly turned to asymmetric tactics to project power and destabilise the West. Hybrid warfare—combining cyber attacks, disinformation campaigns, energy blackmail and sabotage—has become the hallmark of Putin’s foreign policy.
By targeting undersea infrastructure, Russia exploits a critical vulnerability in European resilience. These cables and pipelines are notoriously difficult to protect. Unlike land-based assets, which benefit from national security oversight, the seabed is a legal and logistical grey area. NATO nations have committed to increasing surveillance of critical undersea infrastructure, but coverage remains patchy at best.
The latest breaches occurred just days after the NATO Secretary General called on member states to “redouble efforts” in securing their maritime assets. “These are not accidental faults,” a senior Baltic diplomat told The Telegraph on condition of anonymity. “They are probing for weakness. And they are finding it.”
A NATO Dilemma
Despite growing evidence, the geopolitical response remains muted. Article 5—the cornerstone of NATO’s mutual defence clause—is not triggered by sabotage alone, particularly when attribution remains unconfirmed. This ambiguity plays directly into Moscow’s hands. By keeping its fingerprints smudged but visible, the Kremlin avoids outright retaliation while forcing Western leaders to wrestle with their own caution.
The difficulty of attribution is no accident. NATO intelligence officials suspect Russian military assets in Kaliningrad and the Barents Sea are coordinating surveillance and underwater operations across the Baltic. The use of unflagged civilian vessels, or even deep-sea drones launched from innocent-looking merchant ships, makes enforcement and deterrence a near-impossible task.
Still, Europe is not standing still. In March, the EU launched the Critical Seabed Infrastructure Initiative, which aims to map, monitor and defend strategic undersea lines from sabotage and espionage. Germany has committed an additional €1.2 billion over the next five years for maritime security, and Sweden, newly joined to NATO, has redeployed naval assets to monitor its eastern waters. Yet experts warn these efforts may be too little, too late.
“Deterrence requires not just readiness, but clarity,” says Prof. Kristina Jørgensen, a security analyst at Copenhagen University. “The West must draw a line and communicate it unambiguously. If Russia crosses it again, there must be consequences.”
An Energy War in Slow Motion
Beyond the military dimensions, the incidents reflect a broader contest over energy and economic security. Russia has long used energy as a geopolitical lever, turning off gas taps or manipulating supplies to divide and destabilise European unity. With Nord Stream effectively dead, the Kremlin’s strategy has shifted to disrupting alternative flows.
Lithuania and Poland, in particular, have become key corridors for non-Russian gas and fibre-optic connectivity. That they now find themselves under pressure is no coincidence. “Every new pipeline that bypasses Russia is a threat to their leverage,” notes a Baltic intelligence official. “They are reminding us that they can still make trouble.”
Meanwhile, private sector operators are growing jittery. Energy firms and telecom giants have begun lobbying Brussels for greater protection and contingency planning. Insurance costs for undersea projects have risen, and future investments in the Baltic region are being reconsidered in light of the apparent sabotage risk.
The Long Game
What the latest incidents ultimately reveal is that Russia views the Baltic not merely as a strategic flank, but as a battlefield for its war of nerves with the West. While tanks and drones dominate headlines in Ukraine, silent operations beneath the waves may carry just as much weight in shaping Europe’s future security posture.
The question now is whether European leaders are prepared to confront this new front with the seriousness it demands. The costs of inaction—or of waiting for absolute proof—may be measured not only in disrupted cables and broken pipelines, but in shattered unity and deepening vulnerability.
