Ukrainian soldiers guard a gate of an infantry base in Privolnoye, Ukraine, Sunday, March 2, 2014. Hundreds of unidentified gunmen arrived outside Ukraine's infantry base in Privolnoye in its Crimea region. The convoy includes at least 13 troop vehicles each containing 30 soldiers and four armored vehicles with mounted machine guns. The vehicles ? which have Russian license plates ? have surrounded the base and are blocking Ukrainian soldiers from entering or leaving it. (AP Photo/Darko Vojinovic), APTOPIX

Ukrainian soldiers guard a gate of an infantry base in Privolnoye, Ukraine, Sunday, March 2, 2014. Hundreds of unidentified gunmen arrived outside Ukraine's infantry base in Privolnoye in its Crimea region. The convoy includes at least 13 troop vehicles each containing 30 soldiers and four armored vehicles with mounted machine guns. The vehicles ? which have Russian license plates ? have surrounded the base and are blocking Ukrainian soldiers from entering or leaving it. (AP Photo/Darko Vojinovic)

Ukrainian soldiers guard a gate of an infantry base in Privolnoye, Ukraine, Sunday, March 2, 2014. Hundreds of unidentified gunmen arrived outside Ukraine's infantry base in Privolnoye in its Crimea region. The convoy includes at least 13 troop vehicles each containing 30 soldiers and four armored vehicles with mounted machine guns. The vehicles ? which have Russian license plates ? have surrounded the base and are blocking Ukrainian soldiers from entering or leaving it. (AP Photo/Darko Vojinovic)

Ukrainian soldiers guard a gate to their military base in the village of Perevalne, outside Simferopol, Ukraine, Sunday, March 2, 2014. Hundreds of armed men in trucks and armored vehicles surrounded a Ukrainian military base Sunday in Crimea, blocking its soldiers from leaving. (AP Photo/Ivan Sekretarev)

Ukrainian soldiers guard a gate to their military base in the village of Perevalne, outside of Simferopol, Ukraine, on Sunday, March 2, 2014. Hundreds of armed men in trucks and armored vehicles surrounded a Ukrainian military base Sunday in Crimea, blocking its soldiers from leaving. (AP Photo/Ivan Sekretarev)

Ukrainian Orthodox Archbishop Clement stands guarding a gate of a Ukrainian military base in the village of Perevalne, outside of Simferopol, Ukraine, on Sunday, March 2, 2014. Hundreds of armed men in trucks and armored vehicles surrounded the Ukrainian military base Sunday in Crimea, blocking its soldiers from leaving. (AP Photo/Ivan Sekretarev)

Russian solder is seen behind Ukrainian Orthodox Archbishop Clement, foreground, outside of a Ukrainian military base in the village of Perevalne, outside of Simferopol, Ukraine, on Sunday, March 2, 2014. Hundreds of armed men in trucks and armored vehicles surrounded the Ukrainian military base Sunday in Crimea, blocking its soldiers from leaving. (AP Photo/Ivan Sekretarev)

Ukrainian soldier grimaces behind a fence of their military base in the village of Perevalne, outside of Simferopol, Ukraine, on Sunday, March 2, 2014 as Russian soldier guards from outside. Hundreds of armed men in trucks and armored vehicles surrounded the Ukrainian military base Sunday in Crimea, blocking its soldiers from leaving. (AP Photo/Ivan Sekretarev)

Ukrainian soldiers guard the gate of Ukraine's infantry base in Perevalne, Ukraine, Sunday, March 2, 2014. Hundreds of armed men in trucks and armored vehicles surrounded a Ukrainian military base Sunday in Crimea, blocking its soldiers from leaving. The outnumbered Ukrainians placed a tank at the base's gate, leaving the two sides in a tense standoff. (AP Photo/Darko Vojinovic)

Armed men in military fatigues block access to a Ukrainian border guards base not far from the village of Perevalne near Simferopol on March 2, 2014. About 1,000 armed men surrounded the base of the 36th detached brigade of the Ukrainian Navy's coastal guards today in a tense standoff in the flashpoint Crimea peninsula. Ukraine's new leaders announced a full mobilisation of the army today, a day after Moscow officially approved the deployment of its troops to its western neighbour. AFP PHOTO / GENYA SAVILOV