The Russian semi-exclave Kaliningrad, located on the Baltic Sea and separated from the country's mainland by Lithuania, Latvia, and Belarus, has triggered a new crisis in the region.
Lithuania's decision to block the transit of certain goods on the EU sanctions list to Kaliningrad through its territory has once again brought Russia and the West face to face even as the war in Ukraine continues to rage after four months.
While Russia can reach Kaliningrad via the railway over Lithuania, the region surrounded by NATO members has been at the center of discussions in recent days.
A strategic and military asset for Russia, Kaliningrad is also the only Russian port on the Baltic that is ice-free throughout the year.
Kaliningrad was previously part of Germany until the end of World War II. Since then, it has been a remote Russian province.
Currently, Russia has nuclear-capable missiles are deployed in the 223-square-kilometer (86 sq miles) region.
After NATO member Lithuania blocked the transit of these goods to Kaliningrad, Russia warned that its response could be severe.
Lithuania's Foreign Minister Gabrielius Landsbergis said last week that Vilnius was not acting on its own, noting the guidance of the European Commission on the sanctions in place since June 17.
Coal, metal, construction and technology materials are listed on the sanctions list being enforced by Lithuania, which is under the protective aegis of NATO.
In a series of statements, Moscow also slammed the country's rail transit restrictions from Russia to its semi-exclave.
Meanwhile, the US came to Lithuania's support, saying that an attack on one NATO member would be deemed an attack on the entire alliance.
Most railway transit between Russia and Kaliningrad passes through Belarus and Lithuania.
The EU has slapped six sets of sanctions against Moscow since the beginning of Russia's war in Ukraine on Feb. 24.
The packages target, among others, Russian President Vladimir Putin and Foreign Minister Sergey Lavrov and include a ban oil and coal imports and exports of luxury goods. Also they exclude Russian and Belarusian banks from using the international SWIFT system./aa