Estonia summoned Russia's charge d'affaires on July 28 after a Russian border patrol vessel violated its territorial waters earlier in the week, Estonian public broadcaster ERR reported.
According to ERR, this marks the first time in 2025 that a Russian naval vessel has violated Estonia's maritime border.
The Russian vessel Sochi 500, part of the Svetlyak-class patrol series, entered Estonia's territorial waters east of Vaindloo Island without permission early on the morning of July 26, according to the Estonian Defence Forces. The ship remained in Estonian waters for approximately 35 minutes before departing.
Vaindloo Island is Estonia's northernmost point, located in the Gulf of Finland near vital shipping routes and only about 40 kilometers (25 miles) from the Russian maritime border.
Under Estonia's State Border Act, foreign military vessels are allowed to pass through Estonian territorial waters only if conducting an "innocent passage," and must notify the Estonian Foreign Ministry at least 48 hours in advance. The Russian vessel failed to provide such notice, the Estonian military said.
The Estonian Navy monitored the situation in real time, identified the vessel, and confirmed the border violation.
"This is a serious and unacceptable incident," Estonian Foreign Minister Margus Tsahkna said. "That message has been clearly communicated to the Russian charge d'affaires."
The Estonian Foreign Ministry summoned the Russian diplomat on July 28 to deliver a formal note of protest.
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