Russia is currently keeping the world guessing at its possible options to retaliate. The invasion of the Baltic countries is discussed by the Russian ruling elite, as well as repealing the recognition of Lithuania's independence. The invasion option has popular support in Russia as well. Lithuania is expecting that Russia will disconnect it from the regional electric utility network.
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On 8 June 2022 Russian parliamentarian Yevgeny Alexeyevich Fyodorov submitted a bill to the Duma to repeal the recognition by the Russian state of Lithuania's independence. He thought that in this way the other two Baltic states might have their independence reversed too. An academic from the Institute of Commonwealth of Independent States brought up several expansionist devices and suggested that the Baltic States were "making the same mistake as Ukraine, which believed that the Russian Federation would never send troops because the United States was behind it."
Lithuania–Russia relations: https://en.wikipedia.org/wiki/Lithuania%E2%80%93Russia_relations
While there’s no reason to suggest an attack is imminent, the Russian leader appears to delight in keeping the West guessing what his next move will be. Earlier this month, he praised the imperial exploits of Peter the Great, declaring that “a country is either a sovereign or a colony,” comments that did little to reassure the Baltics. Mikhail Kasyanov, a former Russian prime minister under Putin, added more fuel to the fire last week, predicting that “the Baltic states will be next” if Ukraine falls.
THE MOST DANGEROUS PLACE ON EARTH: https://www.politico.eu/article/suwalki-gap-russia-war-nato-lithuania-poland-border/
Nikolai Patrushev, a former KGB spy who is now the secretary of Russia’s Security Council, said Lithuania’s “hostile” actions showed that Russia could not trust the West.
“Russia will certainly respond to such hostile actions,” Patrushev was quoted as saying by state news agency RIA.
“Appropriate measures are being worked out in an interdepartmental format and will be taken in the near future,” he was quoted as saying. “Their consequences will have a serious negative impact on the population of Lithuania.”
Russia tells Lithuania: Your citizens will feel the pain over Kaliningrad: https://english.alarabiya.net/News/world/2022/06/21/Russia-tells-Lithuania-Your-citizens-will-feel-the-pain-over-Kaliningrad
"The situation is more than serious," Kremlin spokesperson Dmitry Peskov told reporters. "This decision is really unprecedented. It's a violation of everything."
Russia's foreign ministry demanded Vilnius reverse what it cast as an "openly hostile" move immediately.
"If cargo transit between the Kaliningrad region and the rest of the Russian Federation via Lithuania is not fully restored in the near future, then Russia reserves the right to take actions to protect its national interests," it said.
Russia warns NATO-member Lithuania over Kaliningrad transit: https://www.swissinfo.ch/eng/russia-warns-nato-member-lithuania-over-kaliningrad-transit/47688302

Activists protesting outside the Lithuanian embassy in Moscow on 21 June against rail curbs in Kaliningrad display posters saying ‘Closing the border? Our army has visa-free’ and ‘Lithuania in queue for decommunisation’. Photograph: Maxim Shipenkov/EPA
Note: The slogans say:
- "Stop the blockade of Kaliningrad",
- "Are you closing the border? Our army has visa-free rights!",
- "Lithuania is next in line for decommunization" (the latter is a direct reference to Putin's well-known speech justifying invasion of Ukraine as "decommunization").
Russia threatens ‘serious consequences’ as Lithuania blocks rail goods: https://www.theguardian.com/world/2022/jun/21/kaliningrad-russia-threatens-serious-consequences-as-lithuania-blocks-rail-goods
Литва ждет, что Россия отключит ее от региональной электросети в ответ на ограничение грузоперевозок в Калининградскую область, сообщил президент Гитанас Науседа в интервью агентству Рейтер.
(Lithuania is expecting that Russia will disconnect it from the regional electric utility network in response to the limits on cargo transport to the Kaliningrad region, said President Gitanas Nausėda in the interview to Reuters.)
Литва не ждет вторжения в ответ на ограничение транзита в Калининград - президент (Lithuania is not expecting an invasion in response to the limits of transit to Kaliningrad - President)