Kremlin watchers believe nuclear action is unlikely, but also note that brinkmanship could escalate even before a bomb is used

The Russian president has threatened to use battlefield nukes in Ukraine, but such a move would achieve little and could set in motion unstoppable full-scale nuclear war with West

Former Russian president charges Ukraine's allies would not risk nuclear war if Kremlin decided to use weapon; Washington has warned of 'catastrophic consequences'

Blinken says Washington has privately made clear 'horrific' repercussions of using WMDs in Ukraine

US president says such a step by Putin, who's losing ground in Ukraine, 'would change the face of war unlike anything since World War II'; 'They'd become even more of a pariah'

Alexander Lukashenko said upgrades to aircraft followed agreement reached in June meeting with Russia's Putin amid tensions with NATO over Ukraine invasion

Minuteman III missile is capable of carrying nuclear warhead; US Air Force says launch is routine and 'not the result of current world events'

Unnamed sources speaking to US media did not specify origin of bombs referred to in the papers; US Attorney General says he 'personally approved' search of Trump's estate

In response, Putin says nukes should 'never be unleashed' since there would be 'no winners' in such war

As treaty set to expire in 2026, US president says Moscow 'should demonstrate' a readiness to negotiate despite its 'brutal and unprovoked aggression in Ukraine'