Ukrainian officials say Aleksandr Vitko, the Russian commander of the Black Sea Fleet, went aboard a blocked Ukrainian warship in Crimea's Sevastopol Harbor on Monday and issued a threat:

"Swear allegiance to the new Crimean authorities, or surrender, or face an attack," he said, according to Vladislav Seleznev, a Ukrainian Defense Ministry spokesman in Crimea who spoke to CNN. He said the Russian commander did not mention an ultimatum deadline.

But a spokesman for the Russian Black Sea Fleet said there are no plans to storm Ukrainian military units in Crimea, according to the Interfax news agency.

In an international reaction, Swedish Foreign Minister Carl Bildt, after leaving an emergency European Union session in Brussels, told CNN on Monday that the EU has agreed that Russia's actions are an "aggression." Bildt also said that Russia must de-escalate, withdraw its forces and engage in dialogue. If that doesn't happen fairly quickly, he added, that would 'take down' EU-Russian relations.

This is not good. It's as if those troops in Sochi decided to just stay in the region post-Olympics.

President Barack Obama said today that Russia's military moves in Crimea violated international law, adding that "no country has a right to send in troops to another country unprovoked."

He said the United States is examining a series of economic and diplomatic steps to "isolate Russia," and he called on Congress to work with his administration on an economic assistance package for Ukraine.

We really need "Putin Intensifies" and "Obama Intensifies" memes.

Heh. I don't want to be responsible for causing an international incident.