Armed men in military fatigues stand guard outside a regional administration building they seized in the eastern Ukrainian city of Slavyansk on April 14, 2014.

U.S. Sticking With Sanctions on Ukraine

Officials say sanctions against Russia are working but Ukraine ‘on brink of civil war.’

Armed men in military fatigues stand guard outside a regional administration building they seized in the eastern Ukrainian city of Slavyansk on April 14, 2014.

Armed men in military fatigues stand guard outside a regional administration building they seized in the eastern Ukrainian city of Slavyansk on Monday. 

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As tensions and violence escalate in Ukraine, the Obama administration is maintaining its stance that sanctions are the best way to deal with Russian intervention.

"Already, the sanctions that we put in place have brought the ruble to an all-time low in terms of its value," said Samantha Power, U.S. ambassador to the United Nations. "The Russian stock market has depreciated by 20 percent. Investors are fleeing, and that's just on the basis of the sanctions that we put in place up to this point. The president has made clear that, depending on Russian behavior, sectoral sanctions against energy, banking, mining could be on the table, and there's a lot in between."

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Power told ABC Sunday, "I think we've seen that the sanctions can bite, and if actions like the kind that we've seen over the last few days continue, you're going to see a ramping up of those sanctions."

On Sunday, the Ukrainian government for the first time sent its security forces to stop pro-Russian fighters from taking over government facilities in eastern Ukraine, Ukrainian officials said. Fighting broke out and those fighters attacked a Ukrainian police station in Slovyansk, the New York Times reported. At least one Ukrainian policeman apparently was killed and several people were injured, the Times said. There were additional media reports of masked pro-Russian fighters seizing other Ukrainian government facilities in the eastern part of the country during the weekend.

Tens of thousands of Russian soldiers are massed inside Russia along Ukraine's eastern border near Donetsk, and some Western officials fear an invasion.

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Viktor Yanukovych, Ukraine's ousted president who fled to Russia more than a month ago, said Sunday that the country is "on the brink of civil war."

The situation in Ukraine was also described as grave at a meeting of the U.N. Security Council Sunday night. CNN reported that Oscar Fernandez-Taranco, U.N. assistant secretary general for political affairs, said Ukraine "teeters on the brink," and "the likelihood of further bloodshed and violent clashes grows by the hour."

Vice President Joe Biden is scheduled to visit Ukraine's capital of Kiev on April 22 to meet with government officials and citizen activists. Biden will attempt to boost the Kiev government's confidence that the United States and its allies will stand with Ukraine and help strengthen its economy. Biden will also offer support for a free and fair presidential election which is scheduled for May 25, a White House official said.