Ukraine crisis: Grip tightens

9.37pm GMT

Summary

• Russian forces in Crimea urged Ukrainian forces to give up their weapons and stand down, as the number of Russian troops and boats on the peninsula continued to grow. Russia built up forces on both sides of the ferry connecting it to Crimea and sent troops across.

• “The facts on the ground in Crimea are deeply troubling,” US president Barack Obama said. “Russia is on the wrong side of history.”

• A US state department spokesperson said any threat to use force by Russia would “constitute a dangerous escalation.”

• Russian prime minister Dmitry Medvedev told US vice president Joe Biden the troops were there to protect Russians in Ukraine.

• Pro-Russia demonstrators surrounded government buildings in at least three Ukrainian cities, hoisting Russian flags and chanting against the government in Kiev.

• Russia’s UN ambassador called an emergency security council meeting and read a letter he said was from deposed Ukrainian president Viktor Yanukovich asking Moscow to take military action. The performance came in for swingeing criticism.

Russia 'demands surrender' of Ukraine's Crimea forces

Ukrainian defence sources have accused Russia's military of demanding the surrender of their forces in Crimea.

Russia's Black Sea Fleet chief Aleksander Vitko threatened a full assault if they did not surrender by dawn on Tuesday, the sources said.

However, Interfax news agency later quoted a Russian spokesman denying that any ultimatum had been issued.

The EU and US are threatening to hit Moscow with sanctions and travel bans over its intervention in Crimea.

Meanwhile, Russia's UN envoy has said ousted Ukrainian President Viktor Yanukovych has asked Russia to use military force in Ukraine.

Vitaly Churkin said in a speech at the UN that Mr Yanukovych had made the request in writing to Russian President Vladimir Putin.

(CNN) -- Russia rejected accusations that it is acting aggressively toward neighbor Ukraine, telling its Western critics Monday to put aside "geopolitical calculations" in favor of the interests of the people in the former Soviet republic.

Moscow has defended its parliament's approval of President Vladimir Putin's use of military force to protect its citizens in the Crimean Peninsula -- an autonomous region of eastern Ukraine with strong loyalty to Russia -- despite its G8 partners condemning its military buildup in the country and demanding that it withdraw

"I repeat: This is a matter of defending our citizens and our compatriots, of defending the most important human right -- the right to life," Russian Foreign Minister Sergey Lavrov said at a U.N. human rights meeting in Geneva, Switzerland.

13:35: 

Keir Giles of the Chatham House think-tank in London writes that Russia's swift military intervention in Crimea is a "fait accompli" reminiscent of its thrust into Georgia in 2008, leaving the West with few effective options.

• Russian fighter jets violated Russian airspace twice during the night, the Ukrainian defence ministry said. It said a Ukrainian interceptor aircraft was scrambled, preventing any “provocative actions”.

• Russian troops have taken over a ferry terminal on the easternmost tip of Crimea in the city of Kerch and Russian armoured cars were lining up on the Russian side of the Kerch Channel. Kerch is about 20km (12 miles) by boat to Russia

• The Russian prime minister, Dmitry Medvedev, has ordered the construction of a bridge connecting Russia to Crimea.

• Pro-Russian protesters have taken over the first floor of a regional government building in the eastern Ukrainian city of Donetsk. A Reuters reporter said protesters have seized the first floor but were unable to go higher because lifts were disabled and stairwell doors shut. Pro-Russian protesters also reportedly stormed a government building in Odessa

13:05: 

Moscow's stock markets have recorded sharp losses as investors take fright over the consequences of Russian military action in Ukraine, AFP reports. At around 1230 GMT, the MICEX stock market was trading down 11.94% while the other main securities index, the RTS, slumped 13.50%.

Alex, in Kiev, Ukraine 

I'm from Kiev. I always loved Russia. I have many friends and relatives in Russia. My parents are from Russia. So I always considered this country as a best friend. But this was until last week. Putin is out of his mind!

13:03: 

More on the protests in Donetsk: A Reuters reporter in a press centre on the fourth floor of the building said the protesters had seized the first floor but were unable to go higher because lifts were disabled and stairwell doors shut.

13:01: BBC News website reader in the Ukraine 

I talked to a friend who lives in Simferopol. I asked her what does she think of the Crimea becoming part of Russia. She responded that she hopes to become Russian soon. I asked her why? She believes that under the current government they have no future, and to be part of Russia, she would be much better off.

12:57: 

Ukraine's acting Prime Minister Arseniy Yatsenyuk stresses to the BBC that his country has no intention of relinquishing Crimea. He says Crimea "is the territory of Ukraine and despite the presence of Russian military, despite the fact that Russian military supports an illegal government, we will tackle this problem. And any attempt of Russia to grab Crimea will have no success at all. Give us some time."

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