The Ukrainian military this week responded to Vladimir Putin's recent nuclear threats with alarm.
A Ukrainian intelligence deputy told The Guardian the risk of Russia using a nuke is "very high."
Still, experts believe the risk of nuclear war is still low.
The Ukrainian military isn't taking Vladimir Putin's nuclear threats lightly.
The Russian president last week in a brazen escalation of his war in Ukraine made a thinly-veiled threat of nuclear warfare, warning that "this is not a bluff."
Several intelligence experts have since said that the threat of nuclear war remains minimal, but Ukraine is sounding the alarm nonetheless. In an interview with The Guardian this week, Vadym Skibitsky, Ukraine's deputy intelligence chief, put the threat of Russia using a nuclear weapon against Ukraine at "very high."
"They will likely target places along the frontlines with lots of [army] personal and equipment, key command centres, and critical infrastructure," Skibitsky said. "In order to stop them we need not just more anti-aircraft systems, but anti-rocket systems."
The Ukrainian military intelligence boss did not provide evidence for his claims, and officials in his organization have repeatedly spread baseless theories, including that Putin is personally ill. US officials are reportedly closely following signs that Russia has changed the location of its nukes or their alert status, with no signs to emerge of that activity as of Thursday.
Putin is poised to announce the annexation of four occupied Ukrainian territories on Friday. Some Russia watchers and military experts have expressed concerns that these annexations will raise the risk of Putin employing a nuclear weapon. The president has repeatedly made nuclear threats since the war began, and Russian Foreign Minister Sergey Lavrov recently said that any territory formally incorporated into Russia will receive the Kremlin's full protection.
"The red lines against fighting on Russian territory will be suddenly crossed," Retired US Army Brig. Gen. Kevin Ryan, a former defense attaché to Russia, said in recent comments to Insider on the implications of the annexations, adding, "NATO weapons will be fighting and shooting inside Russia. And most importantly, the Russian state will be under direct attack. And as we know, that is a trigger for using nuclear weapons."That said, there are also many analysts who believe that Putin's nuclear threats are largely designed to limit Western support for Ukraine."
"Putin's threats of escalation, including his implicit threat of nuclear escalation, are an attempt to frighten the West and deter it from continuing to arm Ukraine by deploying the false myth that the Kremlin leader is most dangerous when he is cornered. The United States and its allies should not fall for this ruse," Brian Whitmore, a nonresident senior fellow at the Atlantic Council's Eurasia Center, recently wrote.
And there is also skepticism that Russia's depleted military could even pull off a tactical nuclear strike.
"The problem for the Russians is that in order to properly exploit the conditions that are created by a tactical nuclear weapon, you need to have forces that are cohesive, coherent, and with a high level of morale," George Barros, a military analyst with the Institute for the Study of War, told Insider in mid-September.
"I don't think the conventional Russian military, at this point, has the capability or the morale to be able to do that," Barros added.