Russia’s Foreign Ministry summoned Lithuania’s envoy to Moscow on Monday to “demand the immediate lifting of restrictions” or face “defensive action”. [Russia’s] “national interests,” she said in a statement. Gregory Karasin, a former senior diplomat who chairs the foreign affairs committee in Russia’s upper house, said the move was “tough” and warned that any response would be “quite decisive”, according to Russia’s Interfax news agency. Lithuania, which controls the only overland railway line connecting Kaliningrad with mainland Russia, began restricting exports of goods covered by EU sanctions in retaliation over the weekend in retaliation for President Vladimir Putin’s invasion. The restrictions affected iron and steel, luxury goods and some other goods, which had been banned in previous sanctions packages, accounting for a quarter of all Russian rail supplies to Kaliningrad, the ministry said. Josep Borrell, the top EU diplomat, fully defended Lithuania’s actions on Monday, saying that while “always worried about Russian retaliation”, Lithuania “was not guilty”. “Lithuania has not taken unilateral national restrictions and is only applying EU sanctions,” he told reporters. “Lithuania is doing nothing more than implementing the commission ‘s guidelines.” Divided between Lithuania and Poland, Kaliningrad has been a source of tension between Russia and Europe since the Baltic states declared their independence from the USSR in 1991, leaving it without a direct land route to Moscow. It is home to the Russian Baltic Fleet, which has nearly 80 warships and submarines. Moscow has also developed nuclear-capable Iskander ballistic missiles in the region, although it has not said whether they have nuclear warheads. Dmitry Medvedev, Russia’s deputy head of the Security Council, warned in April that it would be impossible for the region to remain “non-nuclear” if Finland and Sweden joined NATO, suggesting that possible nuclear development could be formalized. EU sanctions have further isolated Kaliningrad, forcing Russian planes to bypass the Baltic Sea over a ban on the block’s airspace. Lithuania has denied the allegations in a statement issued Friday stating “Similar, baseless allegations concerning Lithuania have been made more than once. “Lithuania is doing nothing. “These are EU sanctions,” said Gabrielius Landsbergis, Lithuania’s foreign minister. “It is done in consultation with the European Commission and in accordance with the European Commission guidelines.”

Landsbergis, speaking on the sidelines of a meeting of EU foreign ministers in Luxembourg on Monday, downplayed the threat of a Russian response. Lithuania also said that the land railway line would remain open for passengers and unauthorized goods. The Kremlin likened the restrictions to an “exclusion” and said it would assess the situation before deciding if and how to respond, Interfax reported. Anton Alikhanov, the governor of Kaliningrad, said the province could send the sanctioned goods across the Baltic, but said the extra cost would make transit economically unsustainable, according to the state-run Ria Novosti news network. Russia could take “quite obvious” measures in response that would be “extremely painful” for Lithuania, he added.