A Crimean, left, and Russian, right, flags fly over the local government building in downtown Simferopol, Ukraine, on Sunday, March 2, 2014. A convoy of hundreds of Russian troops headed toward Simferopol the regional capital of Ukraine's Crimea region on Sunday, a day after Russia's forces took over the strategic Black Sea peninsula without firing a shot. (AP Photo/Ivan Sekretarev)

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

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

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

Russian soldiers walk as a local resident waves with Russian flag outside of 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)

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

A man holds a Russian flag as 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

Russian soldiers sits atop an armored vehicle outside of 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)

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

A man holds a Russian flag as 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

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

Armed men in military fatigues stand near a painted Ukrainian coat of arms symbol as they 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

Unidentified armed men patrol around a Ukraine infantry base in Perevalne, Ukraine, 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. The outnumbered Ukrainians placed a tank at the base's gate, leaving the two sides in a tense standoff. (AP Photo/Darko Vojinovic)

ALTERNATIVE CROP A Russian flag flies in the foreground as unidentified armed men in uniform block a Ukrainian military base near the village of Perevalne, 20 km south of Simferopol, on March 2, 2014. A group of 1,000 armed men were blocking the entrance to a unit of Ukraine's border guards in a tense standoff in the south of the flashpoint Crimea peninsula on March 2, the defence ministry said. "One thousand armed fighters and around 20 trucks are blocking the perimetre of the 36th brigade of border guards... in Perevalne," the ministry said in a statement, as tensions remain high after Russia's parliament approved the deployment of troops in Ukraine. It did not indicate what nationality the armed men were. AFP PHOTO/ GENYA SAVILOV

A Russian flag flies in the foreground as unidentified armed men in uniform block a Ukrainian military base near the village of Perevalne, 20 km south of Simferopol, on March 2, 2014. A group of 1,000 armed men were blocking the entrance to a unit of Ukraine's border guards in a tense standoff in the south of the flashpoint Crimea peninsula on March 2, the defence ministry said. "One thousand armed fighters and around 20 trucks are blocking the perimetre of the 36th brigade of border guards... in Perevalne," the ministry said in a statement, as tensions remain high after Russia's parliament approved the deployment of troops in Ukraine. It did not indicate what nationality the armed men were. AFP PHOTO/ GENYA SAVILOV

Ukrainian marines guard the gates of their base in the eastern Crimea'a port city of Feodosiya on March 2, 2014. Witnesses said Russian soldiers had blocked about 400 Ukrainian marines at a base in Feodosiya and were calling on them to surrender and give up their arms. AFP PHOTO / VIKTOR DRACHEV

Military personnel stand near a Russian-made Kamaz truck in the eastern Crimea'a port city of Feodosiya on March 2, 2014. Witnesses said Russian soldiers had blocked about 400 Ukrainian marines at a base in the eastern port city of Feodosiya and were calling on them to surrender and give up their arms. AFP PHOTO / VIKTOR DRACHEV

A woman takes photos in front of armed servicemen and their armoured personnel carrier in the eastern Crimea's port city of Feodosiya on March 2, 2014. Witnesses said Russian soldiers had blocked about 400 Ukrainian marines at a base in the eastern port city of Feodosiya and were calling on them to surrender and give up their arms. AFP PHOTO / VIKTOR DRACHEV

Unidentified armed men patrol in front of the Crimean Parliament in Simferopol on March 01, 2014. Pro-Russian forces tightened their grip on Crimea on Saturday as the Kremlin vowed to help restore calm on the restive Ukrainian peninsula and Washington warned of "costs" to Moscow should it order in troops.AFP PHOTO/ GENYA SAVILOV

Troops in unmarked uniforms stand guard in Balaklava on the outskirts of Sevastopol, Ukraine, Saturday, March 1, 2014. An emblem on one of the vehicles and their number plates identify them as belonging to the Russian military. Ukrainian officials have accused Russia of sending new troops into Crimea, a strategic Russia-speaking region that hosts a major Russian navy base. The Kremlin hasn't responded to the accusations, but Russian lawmakers urged Putin to act to protect Russians in Crimea. (AP Photo/Andrew Lubimov)