Ukraine plans for Crimea withdrawal
Ukraine's government says it is drawing up plans to withdraw its troops from Crimea, where Russia is steadily taking formal control as its armed forces seize military installations across the peninsula.
National security and defence council secretary Andriy Parubiy said that Ukraine will seek UN support to turn Crimea into a demilitarized zone as it seeks to relocate armed forces to the mainland.
Ukraine's military, which is heavily outnumbered in Crimea, has come under increased pressure since the region was nominally incorporated into Russia on Tuesday.
Earlier, masked Russian-speaking troops seized control over Ukraine's naval headquarters in the city of Sevastopol. A Ukrainian navy commander was also detained during that operation.
In a warning to Moscow, US Vice President Joe Biden said America will respond to any aggression against its Nato allies, which include neighbours of Russia.
Standing side by side with a pair of Baltic leaders in Vilnius, Lithuania, Mr Biden said the US was "absolutely committed" to defending its allies, adding that President Barack Obama plans to seek concrete commitments from Nato members to ensure the alliance can safeguard its collective security.
"Russia cannot escape the fact that the world is changing and rejecting outright their behaviour," he said, after meeting Lithuanian President Dalia Grybauskaite and Latvian President Andris Berzins.
Earlier today, masked Russian-speaking troops seized control over Ukraine's naval headquarters in the city of Sevastopol. A Ukrainian navy commander was also detained during the operation.
The several hundred militiamen who captured the base in Sevastopol met no resistance. Sevastopol is also the home port of Russia's Black Sea Fleet, and tens of thousands of Russian-led troops are now patrolling Crimea.
It came a day after a confrontation between Ukrainian soldiers and pro-Russian militia left two dead.
The Russian-speaking troops, who arrived on the base after the storming, wore helmets, flak jackets and uniforms with no identifying insignia. By afternoon, they were in full control of the naval headquarters, a set of three-storey boxy white concrete buildings with blue trim. It was not immediately clear how many, if any, Ukrainian servicemen remained on the base.
Ukraine's Defence Ministry said no-one was injured in the raid, which it said was led by pro-Russian militiamen and Cossacks.
The ministry said in its statement that Rear Admiral Sergei Haiduk was detained by unknown people after the storming of the fleet headquarters. The Russian state Itar-Tass news agency reported that he was being questioned by Crimean prosecutors.
Ukraine's defence minister and deputy prime minister had planned to travel to Crimea today in what they said was a bid to avert an escalation in hostilities.
The prime minister in Crimea warned after the announcement of their departure that they would be turned back, however.
"They are not welcome in Crimea," Sergei Aksyonov was quoted as saying by the Interfax news agency. "They will not be allowed to enter Crimea. They will be sent back."
Interfax later cited Welfare Minister Lyudmila Denisova as saying the officials had been denied entry to Crimea. She said an emergency session of the National Security and Defence Council will held in response.
At the Ukrainian navy headquarters, an Associated Press photographer said the militiamen took down the gate and made their way on to the base. They then raised the Russian flag on the square by the headquarters.
The unarmed militiamen waited for an hour on the square and, following the arrival of the commander of the Russian Black Sea Fleet, they took over the building.
The AP photographer was able to enter the headquarters and saw the militia roaming around while the Ukrainian servicemen were packing up and leaving.
Yesterday, President Vladimir Putin signed a treaty to incorporate Crimea into Russia following a referendum on Sunday in which residents of the region overwhelmingly backed the move.
Jubilant crowds in Moscow and other cities across Russia hailed the annexation, while Ukraine's new government called Mr Putin a threat to the "civilised world and international security", and the US and the European Union threatened tougher sanctions against Moscow. On Monday, Washington and Brussels targeted Russian and Crimean officials with visa bans and asset freezes.
Russian news agencies today cited Constitutional Court chairman Valery Zorkin as saying the treaty signed by Mr Putin has been ruled valid, thus formally clearing another hurdle for Moscow to annex Crimea. The treaty now only requires ratification by the Russian parliament.
A Ukrainian serviceman and a member of a militia were killed by gunfire in the incident in Crimea yesterday.
It is unclear whether the militiaman was a Ukrainian citizen. Although Moscow has insistently denied it has not deployed its own troops in Crimea, people in the peninsula have reported seeing a large number of military vehicles with Russian plates.
Thousands of troops under apparent Russian command took over Crimea two weeks before Sunday's hastily called referendum, seizing Ukrainian military bases, blockading others and pressuring Ukrainian soldiers to surrender their arms and leave.
Mr Putin insisted Russia's military presence in Crimea was limited to those stationed under the terms of a treaty with Ukraine that allows Russia to have up to 25,000 troops at its Black Sea fleet base.
Ukraine claims that Russia deployed further forces, however, and expressly went against its request for troops to remain confined within their barracks.
Later, Mr Parubiy said Ukraine will hold joint military exercises with the United States and Britain.
The security chief said it will hold manoeuvres with the countries which signed the 1994 Budapest Memorandum. He did not give any specifics.
The document was signed by the US, Britain and Russia to guarantee Ukraine's territorial integrity after it had surrendered its share of Soviet nuclear arsenals to Russia.
Ukraine has accused Russia of breaching the agreement by taking over the Crimean peninsula.