Ukraine's interim prime minister came to the United Nations Thursday for help in preventing Russia from annexing the Crimean peninsula through a controversial referendum set for Sunday.
In a dramatic confrontation at the U.N. Security Council, Ukraine's Arseniy Yatsenyuk turned toward Russian Ambassador Vitaly Churkin and bluntly asked whether "Russians want war."
Churkin replied that neither his government nor his people want war. He said, "I am convinced that Ukrainians don't want this either. We don't want any further exacerbation of the situation."
Despite Churkin's assertions, Moscow on Thursday acknowledged deploying thousands more troops and military hardware near the Ukrainian border. In announcing the move, Russia's Defense Ministry said the maneuvers will continue for two weeks.
Moscow, which earlier this month sent thousands of military personnel into Ukraine, is backing the referendum Sunday that was called to decide whether Crimea should secede from Ukraine and possibly join the Russian Federation.
U.S. and European leaders accuse Russia of interfering in Ukraine's internal affairs. They say the vote is illegal and have threatened Moscow with economic and diplomatic sanctions if Crimea leaves.
In a statement Thursday, acting Ukraine President Oleksandr Turchynov warned that the Russian forces massed near the border appear "ready to intervene at any time."
Washington's U.N. ambassador, Samantha Power, addressing the Security Council Thursday, called for "a climate of restraint," and for "peaceful dialogue to replace [Russian] coercion."
She also accused Russia of pursuing a course of military action "from the outset" of the crisis, which erupted in full in late February when pro-Russian President Viktor Yanukovych -- facing weeks of anti-government protests -- fled the country.
Additionally, she linked Moscow directly to pro-Russian efforts inside Crimea "to take control of Ukrainian border posts, and to "surround Ukrainian military facilities."
In Washington, Secretary of State John Kerry testified at a U.S. Senate hearing, reiterating the U.S. position that the referendum violates the constitution of Ukraine, as well as international law and the charter of the United Nations. He estimated Russia may have 20,000 troops in Crimea.
Kerry later flew to London, for a face-to-face meeting on Ukraine with his Russian counterpart, Sergei Lavrov.
Earlier this week, as tensions mounted over the standoff, NATO announced its own deployment of fighter jets and surveillance aircraft in European territories bordering Russia.