By Jeremy Herb - 03/03/14 12:00 PM EST
Ukraine says that Russian forces controlling Crimea are demanding the surrender of two Ukrainian warships, threatening an escalation of the crisis, according to the Associated Press.
Ukrainian Defense Ministry spokesman Maksim Prauta said four Russian ships are blocking a Ukrainian anti-submarine warship and command ship in the Sevastopol harbor in Crimea.
BBC reported Monday that the Russian military has also given Ukrainian forces throughout Crimea an ultimatum to surrender before 10 p.m. EST or face an assault, citing Ukrainian defense sources.
Alexander Vitko, the head of Russia’s Black Sea Fleet, set the deadline and threatened an attack “across Crimea."
A Black Sea Fleet spokesman, however, later Monday denied reports of any ultimatum through the Interfax news agency, according to the BBC.
State Department spokeswoman Jen Psaki said that she did not have independent confirmation of the reported ultimatum.
Russian troops have entered Crimea and are said to have effectively taken control of the region.
The Obama administration and Western countries have condemned Russia’s actions, calling it a violation of Ukraine’s sovereignty and territorial integrity.
So far, there have been no reports of shots fired in Crimea.
— Justin Sink contributed.