REUTERS

"This assertion by Russia FM Lavrov is absolutely absurd. [The] Budapest Memorandum requires Moscow not to use or threaten any force – not just nuclear weapons – against Ukraine. Lavrov is not stupid; he knows this," Pifer wrote on Twitter on January 15.

Read alsoFM Lavrov: Russia "respects" Ukraine's post-Crimea territory"Russia['s] use of military force against Ukraine to illegally seize Crimea and provoke conflict in Donbas poses [a] big problem for Russia-West relations," he added.

As UNIAN reported earlier, Lavrov said on January 15 it was Ukraine that had violated the Budapest Memorandum by allowing the Maidan [a wave of demonstrations and civil unrest in Ukraine], rather than Russia, which "had never used" nuclear weapons against the Ukrainian state.