KIEV, Ukraine (AP) — Russia pressed hard Monday for Ukrainian politicians to return to the Feb. 21 agreement that promised a new unity government — with fugitive President Viktor Yanukovych back in power — would rule until an early election no later than December. 
 
 Unidentified gunmen stand outside entrance to the General Staff Headquarters of the Ukrainian Navy in Sevastopol, Ukraine, Monday, March 3, 2014. Pro-Russian soldiers seem to further cement their control... (Associated Press) 
 
 A Ukrainian soldier stands guard at the gate of a military base in the port of Kerch, Ukraine, Monday, March 3, 2014. Pro-Russian troops controlled a ferry terminal on the easternmost tip of Ukraine's... (Associated Press) 
 
 A Ukrainian armored personnel carrier is stationed behind the gate of a military base in the port of Kerch, Ukraine, Monday, March 3, 2014. Pro-Russian troops controlled a ferry terminal on the easternmost... (Associated Press) 
 
 Ukrainian Prime Minister Arseniy Yatsenyuk, left, and British Foreign Secretary William Hague pose for a photograph prior to their meeting in Kiev, Ukraine, Monday, March 3, 2014. Pro-Russian troops took... (Associated Press) 
 
 A ship sails by the port of Kerch, Ukraine, Monday, March 3, 2014. Pro-Russian troops controlled a ferry terminal on the easternmost tip of Ukraine's Crimea region close to Russia on Monday, intensifying... (Associated Press) 
 
 Russian solder is seen behind Ukrainian Orthodox Archbishop Clement, foreground, outside of a Ukrainian military base in the village of Perevalne, outside of Simferopol, Ukraine, on Sunday, March 2, 2014.... (Associated Press) 
 
 Ukrainian soldiers stand guard at the gate of a military base in the port of Kerch, Ukraine, Monday, March 3, 2014. Pro-Russian troops controlled a ferry terminal on the easternmost tip of Ukraine's Crimea... (Associated Press) 
 
 Ukrainian Prime Minister Arseniy Yatsenyuk, left, shakes hands with British Foreign Secretary William Hague in Kiev, Ukraine, Monday, March 3, 2014. Pro-Russian troops took over a ferry terminal on the... (Associated Press) 
 
 Russian solders walk as a local resident waves with Russian flag outside of a Ukrainian military base in the village of Perevalne, outside of Simferopol, Ukraine, on Sunday, March 2, 2014. Hundreds of... (Associated Press) 
 
 Pro Russian soldiers wait outside a Ukrainian military base in the port of Kerch, Ukraine, Monday, March 3, 2014. Pro-Russian troops controlled a ferry terminal on the easternmost tip of Ukraine's Crimea... (Associated Press) 
 
 But the proposal seemed to be a non-starter as diplomats met in Brussels, Kiev and Geneva and warnings about the dangers of Russia's military actions were issued from European capitals. 
 
 On the ground, pro-Russian troops held all Ukrainian border posts Monday in Crimea, as well as all military facilities and a key ferry terminal, cementing their stranglehold on the strategic Ukrainian peninsula. 
 
 "This is a question of defending our citizens and compatriots, ensuring human rights, especially the right to life," Russian Foreign Minister Sergey Lavrov said in Geneva, where he was attending U.N. meetings. 
 
 There have been no reports, however, of any hostilities toward Russian-speakers in Ukraine during the country's four months of political upheaval. 
 
 Tension between Ukraine and Moscow rose sharply after Yanukovych was pushed out by a protest movement made up of people who wanted closer ties with the European Union, more democracy and less corruption. Yanukovych fled to Russia last month after more than 80 demonstrators were killed — mostly by police — near Kiev's central square but insists he is still president. 
 
 In Kiev, Ukraine's new prime minister admitted his country had "no military options on the table" to reverse Russia's military move into its Crimea region, where Ukraine's military admitted that pro-Russian troops have surrounded or taken over "practically all" its military facilities. 
 
 While Prime Minister Arseniy Yatsenyuk appealed Monday for outside help and insisted that Crimea still remained part of his country, European foreign ministers held an emergency meeting on a joint response to Russia's military move that could include economic sanctions. But there was no immediate response to the Russian statement, which would void the new government that Ukraine installed just last week. 
 
 "Any attempt of Russia to grab Crimea will have no success at all. Give us some time," Yatsenyuk said at a news conference with British Foreign Secretary William Hague in Kiev. 
 
 But he added that "for today" there were "no military options on the table." He said his country was "urgently" asking for economic and political support from other countries. 
 
 "Crisis diplomacy is not a weakness, but it is now more important than ever for us not to fall into the abyss of a military escalation," German Foreign Minister Frank-Walter Steinmeier said in Brussels. 
 
 In the meantime, Russian forces were clearly in charge in Crimea, home to 2 million mostly Russian-speaking people and landlord for Russia's critical Black Sea Fleet at Sevastopol. 
 
 In addition to seizing barracks and border posts, troops also controlled a ferry terminal in the Ukrainian city of Kerch, just 20 kilometers (12 miles) across the water from Russia. That intensified fears in Kiev that Moscow will send even more troops into the peninsula via that route. 
 
 The soldiers at the terminal refused to identify themselves Monday, but they spoke Russian and their vehicles had Russian license plates. 
 
 Border guard spokesman Sergei Astakhov said the Russians were demanding that Ukrainian soldiers and guards transfer their allegiance to Crimea's new pro-Russian local government. 
 
 "The Russians are behaving very aggressively, they came in by breaking down doors, knocking out windows, cutting off every communication," he said. 
 
 He said four Russian military ships, 13 helicopters and 8 transport planes had arrived in Crimea in violation of agreements that permit Russian to keep its naval base at Sevastopol. 
 
 Now, fears in the Ukrainian capital of Kiev and beyond are that Russia might seek to expand its control by targeting and seizing other parts of Ukraine, especially in its pro-Russian east. 
 
 "The world cannot just allow this to happen," Hague said, but he ruled out any military action. "The U.K is not discussing military options. Our concentration is on diplomatic and economic pressure." 
 
 Ukraine is also struggling on the financial front. The treasury is almost empty and its currency is under pressure after years of running large deficits. The International Monetary Fund said a fact-finding mission would visit Ukraine starting Tuesday for 10 days. Ukraine has asked the IMF for rescue loans and says it needs $35 billion to pay its bills over the next two years. 
 
 Market reaction to the Russian invasion of Crimea was immediate Monday. In European trading, gold and oil rose while the euro and stock markets fell. The greatest impact was felt in Moscow, where the main RTS index was down 12 percent at 1,115 and the dollar spiked to an all-time high of 37 rubles. 
 
 Russia's central bank hiked its main interest rate 1.5 percentage points Monday to 7 percent, trying to stem financial outflows. 
 
 Gazprom, the Russian energy giant, was also big loser, its share price down 13 percent as investors worried about how it would get its gas to Europe if hostilities kept up, since much of it goes through Ukrainian pipelines. 
 
 Outrage over Russia's military moves has mounted in world capitals, with U.S. Secretary of State John Kerry calling on Russian President Vladimir Putin to pull back from "an incredible act of aggression." Kerry is to travel to Ukraine on Tuesday. 
 
 Putin has rejected calls from the West, insisting that Russia has a right to protect its interests and those of Russian-speakers anywhere in Ukraine. His confidence is matched by the knowledge that Ukraine's 46 million people have divided loyalties — while much of western Ukraine wants closer ties with the 28-nation European Union, its eastern and southern regions like Crimea look to Russia for support and trade. 
 
 Faced with the Russian threat, Ukraine's new government has moved to consolidate its authority, naming new regional governors in the pro-Russia east, enlisting the support of the country's wealthy businessmen and dismissing the head of the country's navy after he declared allegiance to the pro-Russian government in Crimea. 
 
 NATO held an emergency meeting in Brussels and the U.S., France and Britain debated the possibility of boycotting the next Group of Eight economic summit, to be held in June in Sochi, the host of Russia's successful Winter Olympics. 
 
 ___ 
 
 Bennet reported from Kerch, Ukraine. Yuras Karmanau from Kiev, Raf Casert and Juergen Baetz from Brussels and Danica Kirka in London contributed to this report. ||||| Story highlights The United States suspends bilateral trade talks with Russia 
 
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 Russia showed no signs of backing down Monday even as world leaders threatened sanctions and sternly rebuked the country for sending troops into Ukraine. 
 
 At an emergency U.N. Security Council meeting to discuss the unfolding crisis, Ukraine's envoy asked for help, saying that Russia had used planes, boats and helicopters to flood the Ukrainian peninsula of Crimea with 16,000 troops in the past week. 
 
 "So far, Ukrainian armed forces have exercised restraint and refrained from active resistance to the aggression, but they are in full operational readiness," Ukrainian Ambassador Yuriy Sergeyev said. 
 
 As diplomats at the meeting asked Russia to withdraw its troops and called for mediation to end the crisis, Russian Ambassador Vitaly Churkin insisted his country's aims were preserving democracy, protecting millions of Russians in Ukraine and stopping radical extremists. 
 
 He said ousted President Viktor Yanukovych remains Ukraine's elected leader and has asked Russia to send troops. 
 
 The Russian envoy read a letter from Yanukovych at the U.N. meeting, describing Ukraine as a country "on the brink of civil war," plagued by "chaos and anarchy." 
 
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 "People are being persecuted for language and political reasons," the letter said. "So in this regard, I would call on the President of Russia, Mr. Putin, asking him to use the armed forces of the Russian Federation to establish legitimacy, peace, law and order, stability and defending the people of Ukraine." 
 
 U.S. Ambassador Samantha Power said Russia's claims about the situation in Ukraine are untrue and warned that sending military forces "could be devastating." 
 
 Yanukovych, she said, abandoned his post last month and was then voted out of office by Ukraine's democratically elected parliament. 
 
 "Russian military action is not a human rights protection mission," Power said. "It is a violation of international law." 
 
 Earlier Monday, global stocks slipped on fears things could get worse, and diplomats grasped for a way to stop the situation from escalating. 
 
 British Foreign Secretary William Hague called the situation Europe's most serious crisis of the still-young 21st century. 
 
 And U.S. President Barack Obama said the United States is examining a series of economic and diplomatic steps to "isolate Russia," and he called on Congress to work with his administration on an economic assistance package for Ukraine. 
 
 Tensions mount 
 
 In Crimea, more Russian troops arrived, surrounding military posts and other facilities and taking effective control of the peninsula from Ukrainian authorities. What they planned to do next remained unclear. 
 
 Analysts told CNN the apparently growing presence of Russian troops in Crimea means there's a risk the tense standoff could escalate. 
 
 "There are lots of unintended consequences when you have armed men staring at each other in places like you do in Crimea," said Michael McFaul, the former U.S. Ambassador to Russia. "So I think we all need to be very vigilant and worry about the worst case scenario, because it's no one's interest ... to see all out civil war in this country in the heart of Europe of 50 million people." 
 
 Putin's moves into Ukraine come as the Russian leader struggles to deal with a political crisis in the neighboring country that didn't unfold as his government hoped, according to Russia analyst Jill Dougherty, formerly CNN's Moscow bureau chief. 
 
 "Putin has been trying to figure out what to do. So now he's taking these steps," Dougherty said. "And I think that he probably thinks that they're carefully calibrated. But he really is playing with fire." 
 
 In one ominous incident, a Ukrainian Defense Ministry spokesman said the commander of Russia's Black Sea fleet boarded a blocked Ukrainian warship and issued a threat. 
 
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 "Swear allegiance to the new Crimean authorities, or surrender, or face an attack," he said, according to the spokesman, Vladislav Seleznyov. 
 
 But a spokesman for the Russian Black Sea Fleet said there are no plans to storm Ukrainian military units in Crimea, according to the state-run Interfax news agency. 
 
 And one Crimean official has reportedly described the situation there as quiet. 
 
 Despite the assurances, stocks fell around the world, with Russian stocks leading the way as investors parsed the day's developments. Markets declined in Asia, Europe and the United States, where the benchmark Dow Jones fell 153 points Monday. 
 
 State Department spokeswoman Jen Psaki said Monday that sanctions against Russia weren't just possible, but likely. 
 
 Ukraine's shaky new government has mobilized troops and called up military reservists. 
 
 In Kiev, interim Prime Minister Arseniy Yatsenyuk, who has accused Moscow of declaring war, vowed that his West-leaning government would not give up the region. 
 
 "Nobody will give Crimea away. ... There are no grounds for the use of force against civilians and Ukrainians, and for the entry of the Russian military contingent," he said. "Russia never had any grounds and never will." 
 
 Worried West 
 
 The tensions have worried the West, and Russia's G8 partners have condemned Moscow's military buildup in Crimea. The world's seven major industrialized powers also suspended preparations for the G8 summit in Sochi, Russia, in June. 
 
 Their finance ministers announced some economic support for cash-strapped Ukraine. 
 
 "We are also committed to mobilize rapid technical assistance to support Ukraine in addressing its macroeconomic, regulatory, and anti-corruption challenges," the finance ministers said in a written statement. 
 
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 U.S. Secretary of State John Kerry, due in Kiev Tuesday, said several foreign powers are looking at economic consequences if Russia does not withdraw its forces. 
 
 The United States has suspended upcoming trade and investment talks with Russia due to the events in Ukraine, a spokesman for the U.S. trade representative said Monday. 
 
 Obama said Monday that Russia should consider international condemnation of its military moves in Ukraine, adding that "over time, this will be a costly proposition" due to sanctions and isolation that will result if the situation continues or worsens. 
 
 Kerry will offer Ukraine a "specific" package of U.S. economic aid when he travels to Kiev for talks Tuesday, Obama said. 
 
 German Chancellor Angela Merkel's office said Putin had accepted a proposal to establish a "fact-finding mission" to Ukraine, possibly under the leadership of the Organization for Security and Co-operation in Europe, and to start a political dialogue. 
 
 East vs. West 
 
 Ukraine, a nation of 45 million people sandwiched between Europe and Russia's southwestern border, has been in chaos since Yanukovych was ousted on February 22 after bloody street protests that left dozens dead and hundreds wounded. 
 
 Anti-government demonstrations started in late November, when Yanukovych spurned a deal with the EU, favoring closer ties with Moscow instead. 
 
 Ukraine has faced a deepening split, with those in the west generally supporting the interim government and its European Union tilt, while many in the east prefer a Ukraine where Russia casts a long shadow. 
 
 Nowhere is that feeling more intense than in Crimea, the last big bastion of opposition to the new political leadership. Ukraine suspects Russia of fomenting tension in the autonomous region that might escalate into a bid for separation by its Russian majority. 
 
 Ukrainian leaders and commentators have compared events in Crimea to what happened in Georgia in 2008. Then, cross-border tensions with Russia exploded into a five-day conflict that saw Russian tanks and troops pour into the breakaway territories of South Ossetia and Abkhazia, as well as Georgian cities. Russia and Georgia each blamed the other for starting the conflict. 
 
 Moscow has defended its parliament's approval of Putin's use of military force to protect its citizens in the Crimean Peninsula, an autonomous region of eastern Ukraine with strong loyalty to Russia. 
 
 But Ukraine's ambassador to the U.N. says Russia's reasoning for a possible invasion is fake. 
 
 "There is no evidence that the Russian ethnic population or Russian-speaking population is under threat," Sergeyev told CNN. 
 
 The Russian parliament, or Duma, is also considering a law that would allow for the annexation of Crimea, according to the parliament's website. 
 
 "Now they are trying to create new legal basis to prove annexation of the territory they're now occupying," Sergeyev said. ||||| Pro Russian soldiers wait outside a Ukrainian military base in the port of Kerch, Ukraine, Monday, March 3, 2014. Pro-Russian troops controlled a ferry terminal on the easternmost tip of Ukraine's Crimea... (Associated Press) 
 
 Russian solders walk as a local resident waves with Russian flag outside of a Ukrainian military base in the village of Perevalne, outside of Simferopol, Ukraine, on Sunday, March 2, 2014. Hundreds of... (Associated Press) 
 
 Ukrainian Prime Minister Arseniy Yatsenyuk, left, shakes hands with British Foreign Secretary William Hague in Kiev, Ukraine, Monday, March 3, 2014. Pro-Russian troops took over a ferry terminal on the... (Associated Press) 
 
 Ukrainian soldiers stand guard at the gate of a military base in the port of Kerch, Ukraine, Monday, March 3, 2014. Pro-Russian troops controlled a ferry terminal on the easternmost tip of Ukraine's Crimea... (Associated Press) 
 
 Russian solder is seen behind Ukrainian Orthodox Archbishop Clement, foreground, outside of a Ukrainian military base in the village of Perevalne, outside of Simferopol, Ukraine, on Sunday, March 2, 2014.... (Associated Press) 
 
 A ship sails by the port of Kerch, Ukraine, Monday, March 3, 2014. Pro-Russian troops controlled a ferry terminal on the easternmost tip of Ukraine's Crimea region close to Russia on Monday, intensifying... (Associated Press) 
 
 Ukrainian Prime Minister Arseniy Yatsenyuk, left, and British Foreign Secretary William Hague pose for a photograph prior to their meeting in Kiev, Ukraine, Monday, March 3, 2014. Pro-Russian troops took... (Associated Press) 
 
 A Ukrainian armored personnel carrier is stationed behind the gate of a military base in the port of Kerch, Ukraine, Monday, March 3, 2014. Pro-Russian troops controlled a ferry terminal on the easternmost... (Associated Press) 
 
 A Ukrainian soldier stands guard at the gate of a military base in the port of Kerch, Ukraine, Monday, March 3, 2014. Pro-Russian troops controlled a ferry terminal on the easternmost tip of Ukraine's... (Associated Press)
– Russia is hitting back at earlier reports that it had issued an ultimatum to Ukraine, with RT quoting a Defense Ministry spokesman as saying it's "total nonsense." "We’re interested in keeping friendly relations with the people of Ukraine and in preserving stability," another defense source says. Interfax first published the report—which said Russia would attack if all Ukrainian forces aren't out of the Crimea region by 5am tomorrow (meaning 10pm today EST)—citing sources in Ukraine's defense ministry, according to CNN. "If they won't surrender," the report said, "there will be a military storm on all UA (Ukraine Armed) military forces." The source said Russian troops were directly demanding surrender at various military bases in Crimea. A Ukraine Defense Ministry spokesperson also told the AP that Russian ships have trapped two Ukrainian warships in Sevastapol's harbor, and are demanding their surrender. Indeed, Ukraine's prime minister says that pro-Russian troops had surrounded or taken "virtually all" of the country's military facilities. In other developments: Russia is demanding that Ukraine reinstate a unity government negotiated on Feb. 21—which would mean re-installing Viktor Yanukovich as president. The idea appears to be a non-starter with the diplomats gathered in Brussels, however. Russia plans to press ahead with plans to build a bridge linking Russia with Crimea, Dmitry Medvedev said today, following a phone call discussing the crisis with Joe Biden, Sky News reports.