Oddly enough, it is the war in Ukraine that has dragged on into its third year and failures on the Ukrainian front that can force Putin’s Russia to attack the Baltic countries as well. Russia has long shown that its leadership is completely inadequate and its actions are not particularly amenable to rational logic. These NATO countries are very vulnerable from a geographical point of view to Russia. It will be very difficult for NATO countries to deploy their forces and it will take a very long time. Russia may take such a reckless step to force Europe to negotiate peace with it in Ukraine on its terms.
On the other hand, Russia is very interested in the Suwalki corridor, which is located between Poland and Lithuania and connects Belarus with the Kaliningrad region of Russia. This became very relevant when Sweden and Finland recently became new NATO members and the Baltic Sea effectively became an internal sea of NATO countries. Therefore, the seizure of the Suwalki corridor recently became the subject of conversation between Putin and Lukashenko at their last meeting in Moscow.
So, you have zero proof? Right? I thought so...

And here is the proof. A document prepared by the Ministry of Defense appeared on the website of the Russian government, according to which Russia intends to declare part of the water area in the east of the Gulf of Finland, as well as near the cities of Baltiysk and Zelenogradsk in the Kaliningrad region, as its internal sea waters. The 40-year-old resolution of the USSR Council of Ministers regulating the borders in the Baltic Sea is proposed by the Ministry of Defense to be partially “recognized as invalid.”
Unilateral change of existing borders at the expense of the territories of other states or other deterioration of their geographical position actually means a declaration of war on these states. And to whom is Russia actually declaring war? Finland and one of the Baltic countries. Of course, the possibility cannot be ruled out that Putin, as always, is bluffing. He is used to acting with arrogance and intimidation, but now this could well lead to a full-scale war with NATO, for which Russia is clearly not ready.
https://abn.org.ua/ru/novosti/putin-nachinaet-gibridnuyu-agressiyu-protiv-nato-chto-na-eto-otvetit-severoatlanticheskij-soyuz/