UNITED NATIONS (AP) -- The U.S. ambassador to the United Nations says more than 20,000 Russian troops are in Crimea before a referendum on Sunday that could separate the peninsula from Ukraine and merge it with Russia.
Ambassador Samantha Power said the United States and other nations "call for the suspension of this referendum, which cannot be regarded as legitimate, especially against the background of foreign military intervention."
Power said "Russian forces must return to their bases."
She said the United States is proposing a Security Council resolution on the Crimea crisis and that "Russia has to want a diplomatic solution."
British Ambassador Mark Lyall Grant added that a "free and fair referendum cannot possibly be held where voters are casting their ballots under the barrel of a gun."