Lithuania has earned the wrath of Russian authorities after it enforced a transit ban on goods to Kaliningrad, a move that upholds European Union sanctions on Moscow. On the other hand, Russian officials called the move "illegal" and said they would respond accordingly.Photo by Paulius Peleckis/Getty Images

Tensions between NATO member Lithuania and Russia are growing after the former enforced a transit ban on goods that are meant to be transported to the Russian enclave of Kaliningrad, a strategically significant territory on the Baltic coast.

Russian authorities responded furiously after Lithuania banned the passage of sanctioned goods across its territory and into Kaliningrad. However, the latter said that the decision was merely upholding European Union sanctions and that it had the support of the European bloc.

Transit Ban

Now, the tensions between the two regions threaten to escalate strains between Moscow and the EU, which has already unveiled several packages of sanctions on Russian goods. The situation comes as many experts feared that Kaliningrad would become a flashpoint in tensions between Moscow and Europe in the early days of the war against Ukraine.

The area is Russia's westernmost territory and is 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, as per CNN.

Kremlin spokesman Dmitry Peskov on Monday said that the ban was unprecedented and that Russia considered it an "illegal" move." The official said that it was part of a "blockade" and came amid other Russian officials' threat of a response.

The secretary of the Security Council of the Russian Federation, Nikolai Patrushev, said that Moscow would certainly "respond to such hostile actions." The official noted that measures were already being worked out in an interdepartmental format and will be taken in the near future.

According to CBS News, Kaliningrad was captured by the Soviet Red Army in 1945 and is home to roughly 500,000 people. The region is also home to the Russian military's Baltic fleet and a number of advanced nuclear-capable Iskander missile installations.

EU Sanctions on Russia

The transit ban threatens Russia's movement of goods because Kaliningrad is located on an isolated patch of ground and relies on its rail connection to the rest of Russia for the majority of its civilian imports. The rail line runs straight through Lithuania and then neighboring Belarus.

Lithuania decided to prohibit the transit of all goods subject to EU sanctions imposed on Russia for its invasion of Ukraine via the rail link starting on June 18. The restricted goods include coal, metals, electronics, and construction materials.

During a visit to Kaliningrad on Tuesday, Patrushev, who is considered one of the most powerful figures in President Vladimir Putin's inner circle, called the ban "hostile" and "in violation of the international law."

The governor of Kaliningrad, Anton Alikhanov, said that the transit ban was affecting roughly half of all imports to the territory. In a video posted on Telegram, Alikhanov said that the ban was the "most serious violation of the right to free transit into and out of the Kaliningrad region."

The transit ban comes on top of the EU flight ban of 21 Russian-certificated airlines in April, preventing goods from being flown into Kaliningrad as well. The only remaining uninterrupted method of transit left to the territory now is by way of the sea through international waters, Yahoo News reported.