WASHINGTON — The Obama administration said Monday that any Russian threat to Ukraine's navy would be a "dangerous escalation" of an extremely tense situation.
The State Department said that Washington would hold Moscow directly accountable for such an escalation but did not elaborate on potential consequences. Department spokeswoman Jen Psaki said, however, that she could not confirm if Russia had in fact made such threats.
Earlier Monday, a Ukrainian military spokesman said Russia had issued an ultimatum to the crews of two Ukrainian warships in Crimea, demanding that they immediately surrender or be stormed and seized.
Vladimir Anikin, a Russian defense ministry spokesman in Moscow, dismissed the report of a Russian ultimatum as nonsense, but refused to elaborate.
Secretary of State John Kerry is leaving for Ukraine late Monday and then will travel to France and Italy. He had planned to see his Russian counterpart in Paris, but Psaki said that meeting was no longer certain.
The U.S. and its allies are weighing sanctions on Moscow, in what amounts to a sudden reprise of Cold War sensibilities. Once consideration is whether to bolster defenses in Europe in response to Russia's military advances on Ukraine. Kerry said Sunday that world leaders "are prepared to go to the hilt in order to isolate Russia with respect to this invasion."