Why Kaliningrad, Russia's toehold in Europe, could be the next flashpoint in its war against Ukraine

Why Kaliningrad, Russia's toehold in Europe, could be the next flashpoint in its war against Ukraine

(CNN)Tensions are mounting around the Russian exclave of Kaliningrad

an isolated but strategically significant territory on the Baltic coast that could soon be dragged into the Kremlin's war.

Russia has reacted furiously after Lithuania banned the passage of sanctioned goods across its territory and into Kaliningrad

But Lithuania says it is merely upholding European Union sanctions, and the European bloc has backed it

The row now threatens to escalate strains between Moscow and the EU, which has unveiled several packages of sanctions on Russian goods.

Here's what you need to know about Kaliningrad, its history and its importance to Russia.

Since Russia invaded Ukraine in late February, experts have feared that Kaliningrad could become a flashpoint in tensions between Moscow and Europe

It is Russia's westernmost territory, and the only part of the country surrounded by EU states; Lithuania stands between it and Belarus

a Russian ally nation, while Poland borders it to the south.

On Monday, Kremlin spokesman Dmitry Peskov said the move was unprecedented and that Russia considered it illegal

 "It is part of a blockade, of course," he said. Other Russian officials have threatened a response.

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