Ireland warns Russian vessels and shadow fleet threaten undersea cables

Ireland has warned that Russian vessels and the Russian shadow fleet threaten undersea cables near its coasts. Defence Minister Helen McEntee said in March that protecting against emerging threats in Irish waters, particularly from Russian shadow fleet vessels, is a priority. She described the shadow fleet as ageing, often uninsured tankers carrying Russian oil to evade Western sanctions. Russia rejects the shadow fleet label as a political fabrication.

The presence of shadow fleet vessels in Irish waters has prompted worries about accidental damage and deliberate interference with undersea cables. Concerns have grown that cables around Ireland could face interference because Russian vessels have operated near undersea infrastructure in recent years. In November 2024, the Irish Navy forced Russian ship Yantar out of its exclusive economic zone after monitoring it in the Irish Sea. Two months later, the United Kingdom Defence Ministry said Yantar loitered above vital undersea infrastructure inside UK waters.

The British government accused Yantar in late 2025 of aiming lasers at Royal Air Force pilots tracking its movements in the North Sea. Investigators examined a tanker suspected of shadow fleet ties in December 2024 after Gulf of Finland cable damage. A cargo ship sailing from St Petersburg under the St Vincent and the Grenadines flag damaged cables linking Finland and Estonia in December 2025. A Finnish court convicted the Russian captain and the Azerbaijani boatswain of aggravated sabotage.

They denied wrongdoing, and the conviction remains appealable.

The Irish government says roughly 75 percent of transatlantic subsea cables run through or near Irish waters linking North America and Europe. Subsea cables, which carry internet and phone traffic across oceans, transport almost all data, including messages, calls and trillions of dollars in daily financial transactions. These cables support worldwide communications and economic activity and are increasingly considered at risk of sabotage.

Ireland is a major hub for United States-based tech multinationals such as Google, Microsoft and Meta. Daniel Mulhall, the former Irish ambassador to the United States, said 850 United States multinationals operate in Ireland, many running large data centres. A growing concentration of data centres supports Ireland’s digital economy. Mulhall said Ireland forms part of the Western digital economy, so cyber threats may target or harm Ireland even if it is not the main target.

He called cables the bloodstream of the economy and warned that interference would cause serious economic trouble. He said Ireland can no longer rely on its location because digital infrastructure passes through Irish waters. Mulhall said no country can guarantee cable safety, but collective effort can improve preparations to defend cables against malign actors. He said protecting undersea cables requires international cooperation.

Ireland records the lowest defence spending relative to gross domestic product among European Union states. The Irish navy operates no submarines. Ireland is militarily neutral and does not belong to NATO. Ireland recently expanded naval authority so the navy can board and inspect suspicious vessels.

Tom Clonan, an Irish senator who supports neutrality, said neutrality should not block stronger defence. He described Ireland as Europe’s weakest link for defence across air, maritime, ground and cyber domains.