Ukraine's acting foreign minister says Kiev is doing all it can to resolve the crisis in Crimea peacefully, and Ukraine will not give the region up.
At a press conference in Kiev, Andriy Deshchytsa said Crimea had always been part of Ukrainian territory, and urged Russia to help ensure international observers can operate in Crimea.
He also called for a contact group to be established to end the military standoff with Russia.
Meanwhile, the deputy commander of a military base in Crimea said three dozen armed men crashed a truck through its gates in an attempt to take it over. They cut off power and telephone lines to the base, and urged Ukrainian troops to surrender their weapons and swear allegiance to Russia.
A large demonstration was also held in the Crimean city of Donetsk denouncing the government in Kiev.
The Black sea peninsula has become the main focus of the crisis in Ukraine. It's home to the Russian Black Sea fleet, and most of the residents are ethnic Russians.
