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Timeline: Key events in Ukraine’s political crisis
March 2: Ukraine appeals for international help, fearing a wider Russian invasion. Supporters on both sides take to the streets of Ukrainian cities and of Moscow. The Group of Seven suspends preparations for June's G-8 summit in Russia.
March 3: Ukraine says there are up to 16,000 Russian troops in Crimea. Russia says it has approved troop deployment at the request of Yanukovych. The main Russian stock index falls 12 percent; Russia's central bank raises its main interest rate 1.5 percentage points.
March 6: Crimea's parliament declares the region wants to join Russia and will let voters decide in a March 16 referendum.
March 11: The EU proposes a package of trade liberalization measures to support Ukraine's economy, abolishing most import tariffs on the country's products — a step expected to save the country's exporters 500 million euros ($695 million) annually.
March 12: Obama meets with Yatsenyuk at the White House in a show of support for the new Ukrainian government and declares the U.S. would "completely reject" the Crimea referendum.
March 14: A last-ditch diplomatic effort before the referendum fails in London, where Russian Foreign Minister Sergey Lavrov met with U.S. counterpart John Kerry amid threats of sanctions against Russia if it annexes Crimea.