The chief of Crimea's election commission, Myhkailo Malyshev, said Monday he is moving ahead with preparations for next Sunday's referendum on unification with Russia. He said all registered Crimean voters are eligible to vote.
Russian forces have tightened their grip on Crimea, as authorities in the breakaway territory push their plan to join Moscow.
Ukraine's interim prime minister vowed Sunday not to give up "a single centimeter" of territory. Arseniy Yatsenyuk addressed supporters who rallied in Kyiv to celebrate the 200th birthday of Ukrainian poet and national hero Taras Shevchenko.
Mr. Yatsenyuk is to meet Wednesday with U.S. President Barack Obama in Washington to discuss the standoff over Crimea, a strategic peninsula in southern Ukraine with a Russian-speaking majority.
A Russian lawmaker said the Kremlin had set aside $1.1 billion to rebuild Crimea's industrial infrastructure if the disputed region votes in a March 16 referendum to join Russia.
German Chancellor Angela Merkel told Russian President Vladimir Putin in a phone call Sunday the planned referendum is illegal and violates Ukraine's constitution.