Russia has shut off access to the Sea of Azov from the Black Sea, accusing Ukrainian vessels of traversing its territorial waters without permission, Russian state TV reported on Sunday.
Earlier in the day, a Russian coast guard vessel rammed a Ukrainian navy tugboat, resulting in damage to the ship's engines and hull, the Ukrainian navy said.
The incident happened when two Ukrainian navy artillery boats and a tugboat were transiting from Odessa on the Black Sea to Mariupol in the Sea of Azov, via the Kerch Strait, a narrow passage between Crimea and the Russian mainland.
Russian state TV said its navy had subsequently blocked shipping passing under the Kerch Strait bridge by placing a cargo ship in the way.
A Rossiya 24 correspondent reporting from the area said Russia's tactic had completely blocked the bridge, and that Russian military helicopters were circling overhead.
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New tensions between neighbors
Both sides quickly traded blame over the incident. Russian media cited authorities as saying that Kyiv had sought to "create a conflict situation."
Ukraine insisted it had informed Russia's Federal Security Service (FSB) in advance about the ships' movement.
Kyiv said Moscow had violated the UN Convention on the Law of the Sea and the contract between Kiev and Moscow on the use of the Sea of Azov and the Kerch Strait.Although a 2003 treaty designates the tow areas as shared territorial waters, Russia has been asserting greater
control over the passage since 2015.
This latest dispute has raised concerns about a possible escalation of a wider conflict between the two neighbors.
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Russia annexed the Crimean Peninsula in 2014, and eastern Ukraine has descended into violence, with the West accusing Russia of supporting pro-Moscow separatists in the region.
mm/rc (DPA, Reuters)
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