KERCH, Ukraine - Armed men believed to be Russian soldiers stand near a port in Kerch in Ukraine's Autonomous Republic of Crimea on March 3, 2014. (Kyodo)

SIMFEROPOL, Ukraine - An armed man believed to be a member of the Russian military but not wearing insignia stands outside Ukraine's naval base near Simferopol, the capital of the Autonomous Republic of Crimea, southern Ukraine, on March 2, 2014. (Kyodo)

SIMFEROPOL, Ukraine - Armed men believed to be members of the Russian military but not wearing insignia and Russian residents (R) stand in front of a church adjacent to Ukraine's naval base near Simferopol, the capital of the Autonomous Republic of Crimea, southern Ukraine, on March 2, 2014. (Kyodo)

Ukrainian soldiers guard the entrance of a military base in the small Crimean city of Bakhchisaray on March 3, 2014. Russian troops and military planes were flowing into Crimea today in violation of accords between the two countries, Ukrainian border guards said. Kiev received no warning regarding the troop movements, even though that is required by the international laws regarding the stationing of Russia's Black Sea navy in Crimea. AFP PHOTO / GENYA SAVILOV

A Ukrainian soldier uses binoculars as he stands guard at the entrance of a military base in the small Crimean city of Bakhchisaray on March 3, 2014. Russian troops and military planes were flowing into Crimea today in violation of accords between the two countries, Ukrainian border guards said. Kiev received no warning regarding the troop movements, even though that is required by the international laws regarding the stationing of Russia's Black Sea navy in Crimea. AFP PHOTO / GENYA SAVILOV

TOPSHOTS Armed men block access to a Ukrainian border guards base not far from the village of Perevalne near Simferopol on March 3, 2014. About 1,000 armed men surrounded the base of the 36th detached brigade of the Ukrainian Navy's coastal guards since yesterday in a tense standoff in the flashpoint Crimea peninsula. Russian troops and military planes were flowing into Crimea today in violation of accords between the two countries, Ukrainian border guards said. AFP PHOTO / ALEXANDER NEMENOV

TOPSHOTS Armed men in military armed block access to a Ukrainian border guards base not far from the village of Perevalne near Simferopol on March 3, 2014. About 1,000 armed men surrounded the base of the 36th detached brigade of the Ukrainian Navy's coastal guards since yesterday in a tense standoff in the flashpoint Crimea peninsula. Russian troops and military planes were flowing into Crimea today in violation of accords between the two countries, Ukrainian border guards said. AFP PHOTO / ALEXANDER NEMENOV

TOPSHOTS A man with a Russian flag greets armed men in military fatigues blocking access to a Ukrainian border guards base not far from the village of Perevalne near Simferopol on March 3, 2014. About 1,000 armed men surrounded the base of the 36th detached brigade of the Ukrainian Navy's coastal guards since yesterday in a tense standoff in the flashpoint Crimea peninsula. Russian troops and military planes were flowing into Crimea today in violation of accords between the two countries, Ukrainian border guards said. AFP PHOTO / ALEXANDER NEMENOV

Ukrainian soldier stand behind a fence while unidentified armed men block the headquarters of the Ukrainian Navy in Sevastopol on March 3, 2014. The Russian Black Sea Fleet commander Aleksandr Vitko has issued an ultimatum to the Ukrainian military personnel in Crimea, the Interfax-Ukraine news agency reported. Ukraine accused Russia on Monday of pouring more troops into Crimea as world leaders grappled with Europe's worst standoff since the Cold War and the Moscow market plunged on fears of an all-out conflict. AFP PHOTO/ VIKTOR DRACHEV

(FILES) A file picture taken on October 24, 2003, shows Russian flag flying at the construction site of the dam from the Russian coast to Tuzla isle in Azov sea , just over three miles (5.5 kilometers) away in the Kerch strait. Moscow formally launched today a project to build a bridge to Ukraine's Crimea, as armed men believed to be Russian took the Black Sea peninsula under almost complete control.The decree signed by Medvedev names Russia's state company Avtodor as the main contractor for the project and for engineering studies to be completed by November 2014. AFP PHOTO/DENIS SINYAKOV/VREMYA NOVOSTEY

A protester draped in a Ukrainian flag demonstrates against Russian intervention in Ukraine, during a demonstration in London's Parliament Square, on March 3, 2014. Ukraine's military said Monday that Russia had given its forces an ultimatum to surrender in Crimea or face an all-out assault on the strategic Black Sea peninsula that has been overrun by Kremlin-backed troops. AFP PHOTO/BEN STANSALL

An unidentified armed man in uniform stands guard outside the headquarters of the Ukrainian Navy in Sevastopol on March 3, 2014. Russian forces have given Ukrainian soldiers an ultimatum to surrender their positions in Crimea or face an assault, a Ukrainian defence ministry spokesman said. "The ultimatum is to recognise the new Crimean authorities, lay down our weapons and leave, or be ready for an assault," said Vladyslav Seleznyov, the regional ministry spokesman for the Crimea. AFP PHOTO / FILIPPO MONTEFORTE

A man smokes a cigarette in front of Ukrainian coast guards standing guard at the gateway of their unit in Balaklava, near Sevastopol on March 3, 2014. Ukraine's military said on March 3 that Russia had given its forces an ultimatum to surrender in Crimea or face an all-out assault on the strategic Black Sea peninsula that has been overrun by Kremlin-backed troops. AFP PHOTO/ VIKTOR DRACHEV

Russian Navy ships pass by Sevastopol harbour on March 3, 2014. The Russian Black Sea Fleet commander Aleksandr Vitko has issued an ultimatum to the Ukrainian military personnel in Crimea, the Interfax-Ukraine news agency reported. Ukraine accused Russia on Monday of pouring more troops into Crimea as world leaders grappled with Europe's worst standoff since the Cold War and the Moscow market plunged on fears of an all-out conflic AFP PHOTO/Filippo MONTEFORTE

A Ukrainian national flag flies on the board of Ukrainian navy ship Slavutich at harbor of Sevastopol, Ukraine, Monday, March 3, 2014. The Ukrainian Defense Ministry said that Russian forces that have overtaken Ukraine's strategic region of Crimea are demanding that the ship's crew surrender. (AP Photo/Andrew Lubimov)

The Russian naval landing vessel "Georgiy Pobedonosets" enters one of the bays of Sevastopol, Sunday, March 2, 2014. Russian President Vladimir Putin has defied calls from the West to pull back his troops, insisting that Russia has a right to protect its interests and the Russian-speaking population in Crimea and elsewhere in Ukraine.(AP Photo/Andrew Lubimov)

Unidentified gunmen guard Ukraine's 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)

Unidentified armed men prepare their camp in front of Ukraine's 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)

An unidentified armed man guards the gate of Ukraine's 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)

Unidentified armed men guard the entrance to 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)