Ukraine's interim Prime Minister Arseniy Yatsenyuk appealed to the UN Security Council Thursday for its support to help stop Russia from annexing its Crimea region in a referendum planned for Sunday.
Yatsenyuk told the UN's most powerful organ that his country is facing the military aggression of one of the council's permanent members -- Russia.
"This aggression has no reasons and no grounds. This is absolutely and entirely unacceptable in the 21st century to resolve any kind of conflict with tanks, artillery and boots on the ground," he said.
Yatsenyuk said despite Russia's violation of a number of treaties, Ukraine still believes there is a chance to resolve the dispute peacefully and avoid the secession and annexation of Crimea this Sunday.
Speaking in Russian he addressed Moscow's ambassador, asking him if Russia wants war saying, "We are looking for an answer to the question whether Russians want war. I am sure as prime minister of Ukraine -- which for decades had warm and friendly relations with Russia -- I am convinced that Russians do not want war."
Russia's UN Ambassador Vitaly Churkin replied to Yatsenyuk during his remarks saying, "Russia does not want war and nor do the Russians. And I am convinced that Ukrainians don't want this either. And furthermore, this is something I want to underscore, we do not see any premises to view and interpret the situation in such terms. We don't want any further exacerbation of the situation," said Churkin.
Russia's international isolation was evident, with even its closest ally, China, having taken a firm stance in support of Ukraine's sovereignty and asserting its policy of non-interference in another state's domestic affairs.
Earlier Thursday, the U.S. delegation circulated a draft resolution reaffirming the principles of Ukraine's territorial integrity, sovereignty, and independence and that states that Sunday's referendum is illegal, and urges nations to not recognize the results. The draft text does not name Russia as an aggressor nor explicitly demand it pull its troops back from Crimea.
U.S. Ambassador Samantha Power said her Russian counterpart's remarks seemed to be about validating the referendum and annexation of Crimea.
"This causes us great alarm, which is one of the reasons that we have circulated this resolution, in the hopes of finding a vehicle for showing the extent of Russia's isolation as it pursues a non-peaceful path," said Power.
Diplomats said they expect a Russian veto, but if Moscow's close ally, China abstains, it would demonstrate Russia's extensive international isolation. Several diplomats said they favored holding a vote by Saturday.
Prime Minister Yatsenyuk also met with UN chief Ban Ki-moon Thursday. Ban has repeatedly called on all parties to deescalate the situation and find a solution through political dialogue.
Earlier in the day Secretary of State John Kerry told a congressional hearing the United States and the European Union will respond on Monday with a "serious series of steps" against Russia if a referendum on Ukraine's Crimea region goes ahead on Sunday, U.S. Secretary of State John Kerry said on Thursday.
Kerry told a congressional hearing he hoped to avoid such steps, which include sanctions, through discussions with his Russian counterpart, Sergei Lavrov, in London on Friday.
The Russian Foreign Ministry said Foreign Minister Sergei Lavrov and Kerry discussed proposals for resolving the crisis in Ukraine during a telephone conversation on Thursday.
Lavrov and Kerry, who are due to meet in London on Friday, discussed "the situation in Ukraine, taking into account existing Russian and U.S. proposals to normalize the atmosphere and provide for civil peace," the ministry said.
Russia announced new military operations Thursday near the Ukraine border, prompting acting Ukraine President Oleksandr Turchynov to warn that those forces appear "ready to intervene at any time."
Russian media say the exercises will take place over the next two weeks, as the United States and Western Europe face off with Moscow over the fate of Ukraine's Russian-speaking Crimean peninsula.
In Moscow Thursday, the Russian Defense Ministry acknowledged major operations with armored and airborne forces near its border with eastern Ukraine. The ministry said the maneuvers involve artillery units, assault helicopters and at least 10,000 soldiers.
Earlier this week, NATO announced its own deployment of fighter jets and surveillance aircraft in European territories bordering Russia.
President Barack Obama warned Russia again Wednesday that the West will "apply costs" to Moscow if it continues to interfere in Ukrainian affairs.
Speaking at the White House alongside interim Ukrainian Prime Minister Arseniy Yatsenyuk, Obama said Washington "completely rejects" Crimea's planned referendum Sunday on whether to secede from Ukraine and join Russia. He said the vote, "patched together in a few weeks," is a violation of international law.
Yatsenyuk thanked Washington for its support, and said his government is "absolutely ready and willing" for talks with Moscow, but added that Ukraine will never surrender. He also said his government is preparing to sign an association agreement with the European Union later this month.