Sweden expands checks on Russia’s “shadow fleet” beyond its territorial waters, making half the Baltic a risk zone for Moscow

Coastal states have rights over the exploration and use of marine resources in their EEZs — both living (such as fish) and non-living (like oil and gas). They also hold regulatory power over economic activity in the area and. However, international law still permits freedom of navigation, overflight, and the laying of cables and pipelines by other states within EEZs, similar to in neutral waters.

That means warships and commercial vessels from other countries can pass through Sweden’s EEZ without permission — as long as they respect international law and Sweden’s sovereign rights. While Sweden has the legal authority to enforce environmental protections and fishing regulations in its EEZ, it cannot stop tankers unless they violate specific international or national laws, such as those concerning pollution, documentation, or threats to maritime safety.

A review of maritime charts suggests that if Germany, Poland, Lithuania, Latvia, and Estonia were to implement similar insurance checks, nearly the entire Baltic Sea would become a high-risk zone for Russia’s shadow fleet. Russian authorities appear to recognize this risk — on May 25, reports emerged that Russian tankers are now operating with military escorts.

One such case involved the Russian tanker Jaguar, which Estonia attempted to stop for inspection. A Russian fighter jet intervened and escorted the vessel to Russian territorial waters.

Why the “shadow fleet” poses a threat

The main concern around the “shadow fleet” involves its role in transporting Russian oil and petroleum products to international buyers in circumvention of the $60-per-barrel price cap introduced by the G7, the EU, and Australia in 2022. The fleet has allowed the Kremlin to continue to line its coffers and finance the ongoing full-scale invasion of Ukraine, which entered its fourth year in February 2025.

These vessels, however, are difficult to sanction directly. Many turn off their AIS (automatic identification system) trackers, making them hard to monitor — especially when they frequently change names and flag states mid-voyage, as the Jaguar reportedly did.

Still, authorities can take action on more technical grounds, such as lack of insurance or other necessary documentation. Many shadow fleet vessels are in poor condition — older ships often written off by previous owners and purchased cheaply. As a result, they pose a high risk of environmental disaster.

“The status of the vessels is supposedly lower than is deemed acceptable, with single-hull tankers that are less maintained than legitimate shipping and hence are environmental disasters in the making,” said Swedish military analyst Joakim Paasikivi in comments to The Insider. “There is also a risk that masters and crews are less well trained making the risk for accidents greater.”

Paasikivi noted that some shadow fleet tankers have recently been found operating without valid registration. One ship, the Kiwala, transmitted AIS data claiming it was sailing under Djibouti’s flag, even though Djibouti’s maritime registry had no record of the vessel.

Paasikivi argued that enforcement should extend beyond the ships themselves to the so-called “flag states” that issue fake insurance certificates and documents.

“I believe that ensuring that flag states do due diligence regarding ownership, standard of vessels and crews, and insurance, i.e. making sure that the papers are clear should be enforced, if necessary by sanctions if they fail to do so,” Paasikivi said. “Also, coast states should make sure that vessels in their EEZ — and especially territorial waters — have switched on AIS and have papers in order. Environmental inspections should be made to ensure acceptable standards. Ships not meeting those demands should be arrested — but that is subject to laws, rules, and regulations. The possibility to also prosecute individual masters and crewmembers is part of this.”