Russian military personnel march in Moscow's Red Square during a rehearsal Thursday for the Victory Day military parade that will take place Saturday to celebrate the 70th anniversary of the victory over Nazi Germany in World War II. Ivan Sekretarev/AP hide caption

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Refugees from different cities of the Donetsk region controlled by pro-Russia separatists stay March 12 in a center for refugees in the eastern Ukrainian city of Slavyansk. The cease-fire in eastern Ukraine between Kiev's forces and pro-Russian rebels has been tenuous at best, and residents of the region continue to flee; 1.2 million have been displaced by the fighting. Sergei Supinsky/AFP/Getty Images hide caption

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Cars drive past the Kremlin along the Moscow River last December. Foreign automakers had been ramping up production in Russia, but the country's economic woes have caused car sales to drop sharply. Several foreign automakers have cut back production, and General Motors is pulling out of Russia. Alexander Zemlianichenko/AP hide caption

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A Ukrainian serviceman walks in the village of Pisky in the region of Donetsk controlled by Ukrainian forces on Feb. 26. Oleksandr Ratushniak/AFP/Getty Images hide caption

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Workers stand next to a gas pipeline not far from the central Ukrainian city of Poltava in June 2014. Ukraine imports much of its gas from Russia, which is once again threatening to cut off supplies in a dispute over payments. Sergei Supinsky/AFP/Getty Images hide caption

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