Putin made the declaration in his much-delayed annual state of the nation address to Russia’s National Assembly on Tuesday. ”In a lengthy statement published on its website, Russia’s Foreign Ministry said the decision to suspend participation in the treaty is “reversible,” saying that ” Washington must show political will, make conscientious efforts for a general de-escalation and create conditions for the resumption of the full functioning of the Treaty and, accordingly, comprehensively ensuring its viability. ”What to know about Russia's latest move on nuclear weapons And though a US intelligence assessment in November suggested that Russian military officials discussed under what circumstances Russia would use a tactical nuclear weapon in Ukraine, the US has not seen any evidence that Putin has decided to take the drastic step of using one, officials told CNN