Lithuania's decision to ban the rail-based transit of goods to and from Kaliningrad is "unprecedented" and illegal, and will not be left without a response, Kremlin spokesman Dmitry Peskov has said.
"This decision is truly unprecedented. It is a violation of everything. We understand it to be connected to the relevant decision made by the European Union - to extend sanctions to transit. We also consider it illegal," Peskov said, speaking to reporters on Monday.
"We need a serious, in-depth analysis to work out our response decisions," Peskov said, adding that this work would be carried out over the next few days.
Vilnius began enforcing a ban on the transit of goods subject to EU sanctions between mainland Russia and Kaliningrad on Saturday.
Governor Alikhanov said construction materials, metal products, coal, cement, high tech products and other goods would be affected.
"We consider this to be a most serious violation...of the right to free transit into and out of Kaliningrad region," Alikhanov said in an online video address, and vowed to fight to have the restrictions lifted quickly. In the meantime, he said, ferries between Kaliningrad and St. Petersburg would "handle all the cargo" to prevent local shortages, and advised residents against panic buying.
Lithuanian Foreign Minister Gabrielius Landsbergis has indicated that the rail transit restrictions were introduced "after consultations with the European Commission and under its leadership."
Russian Senator Olga Kovitidi warned that Vilnius's move would "boomerang back on the Baltic countries" and affect the "mobility and opportunities" of their residents. Lithuania has "once against shot itself in the foot" by instituting its blockade, she said.
Meanwhile, Senator Andrey Klimov warned that if Brussels doesn't resolve the situation immediately, it will "disavow for [the Russian side] the legitimacy of all documents on Lithuania's membership in the EU and untie our hands to solve the problem of transit to Kaliningrad any way we choose."
Senator Andrey Klishas echoed his colleagues' concerns, calling the restrictions an attempt to establish a full-on blockade, and "a violation of Russia's sovereignty."
Kaliningrad has a population of about one million people, and is home to Russia's Baltic Fleet. Moscow was forced to dramatically build up the region's air and missile defenses in recent years due to encroachment by NATO forces and the alliance brainstorming on the need to "seize" the Russian exclave.
Lithuania closed its airspace to flights of Russian commercial aircraft to Kaliningrad in February, forcing planes to fly around the region through the Baltic Sea. Last month, Lithuania's parliament moved to recall the country's ambassador and close its consulate general in St. Petersburg.