Citing notes taken by an unnamed American present at a meeting between Russian and US officials in Germany in March, the newspapers said the Russian side claimed the "same conditions" that caused it to invade Ukraine existed in the Baltic states, in apparent reference to the fact that the region has substantial Russian populations.
Russian military representatives said they would consider a "spectrum of responses from nuclear to non-military" if NATO continued to reinforce its Baltic member states, the reports suggested.
Without going into details, Russia also threatened to launch indirect "destabilising actions" in the Baltic states along the lines of its familiar hybrid warfare strategy, it was claimed.
“Russia would hope slowly to entice those Russian populations towards Russia without giving NATO a pretext to deploy troops,” the document seen by the Times says.
Estonia, Latvia and Lithuania have all been NATO members since 2004.
Russian politicians and other public figures regularly air the possibility of nuclear strikes against the Baltic states and others, apparently regarding such discussions as perfectly normal.