Washington (CNN) -- To President Barack Obama and U.S. allies in Europe, Sunday's secession referendum in Crimea is unconstitutional, illegal and a fraud because Russian troops have essentially taken over the southern Ukraine peninsula. To Russian President Vladimir Putin, it is a chance for Crimean residents to decide if they want to realign their region with Moscow after the political strife in Ukraine that ousted the pro-Russian leader last month. Whatever the outcome, the vote planned by Crimea's regional parliament and endorsed by Russia's government will further inflame the Ukrainian crisis as the United States and European Union seek a diplomatic solution while threatening diplomatic and political sanctions.
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People in Crimea, an autonomous region of Ukraine, vote Sunday on joining Russia
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The United States and its European allies reject the referendum as illegal
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To Russia, the ousting of the elected Ukraine government was illegal
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At issue is whether constitutional authority exists in Ukraine
Power said that if the referendum goes forward, the result would get little recognition beyond @placeholder.
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