Crimea declared independence Monday and applied to join Russia while the Kremlin braced for sanctions after the flashpoint peninsula voted to leave Ukraine in a referendum that has sparked the worst East-West crisis since the Cold War.
Officials results from Sunday's poll showed 96.6 percent of the voters in the mostly-Russian speaking region opting to switch to Kremlin rule in the most radical redrawing of the map of Europe since Kosovo's 2008 declaration of independence from Serbia.
"Crimea appeals to the United Nations and to all countries of the world to recognise it as an independent state," said a declaration adopted by the region's Russian-backed assembly.
Ukraine's interim president Oleksandr Turchynov denounced the vote as a "great farce" and watched from a podium as agitated lawmakers approved a partial mobilisation of the army aimed at countering Russian troops' effective seizure of Crimea at the beginning of March.
The defence minister also insisted Ukrainian troops would stay in the strategic Black Sea region.
Most of the international community has rejected the referendum as illegal because Russia had vowed to respect its neighbour's territorial integrity under a milestone 1994 agreement that saw Ukraine renounce its Soviet-era nuclear arms.
- 'Strongest possible signals' -
Bu the government in Crimea announced a series of measures to sever the ties with Ukraine -- including seizing Ukrainian institutions and even plans to set the peninsula on Moscow time.
The White House said US President Barack Obama warned his Russian counterpart Vladimir Putin that Washington and its allies would "never" recognise Crimea's breakaway vote.
Obama warned that "Russia's actions were in violation of Ukraine's sovereignty and territorial integrity and that, in coordination with our European partners, we are prepared to impose additional costs on Russia for its actions," the White House said.
EU foreign policy chief Catherine Ashton also said Europe needed to send the "strongest possible signals" to Russia at a meeting of the 28-nation bloc's foreign ministers Monday.
The ministers are widely expected to approve "targeted" sanctions against Russian or pro-Kremlin Ukrainian leaders that could include both travel restrictions and asset freezes.
The measures -- reportedly affecting top Russian ministers and presidential aides but not Putin himself -- are meant to demonstrate the West's united resolve to punish the Kremlin for its overt show of post-Soviet might.
Putin has signalled no intention to turn back on what he describes as his defence of ethnic Russians who have come under increasing attack from Ukrainian ultranationalists since last month's ouster in Kiev of a pro-Kremlin regime by a far more nationalist but Western-leaning team.
The Kremlin said Putin "emphasised" to Obama that the referendum "was fully in line with the norms of international law and the UN charter".
It said Putin pointed out "the well-known precedent of Kosovo" -- a mostly Muslim region of former Soviet ally Yugoslavia whose independence is backed by Washington but not recognised by the Kremlin.
- 'We're going home' -
Russia's lower house of parliament is expected to debate legislation on Friday simplifying the process under which the Kremlin can annex another part of a sovereign state.
But the overwhelming margin of victory for the pro-Kremlin camp in Crimea underscores the degree of mistrust in the heavily Russified southeastern swathes have for the European leanings of those who rose to power on the back of three months of deadly protests in Kiev.
Alcohol-fuelled celebrations swept cities across the diamond-shaped Black Sea peninsula as Russian flags waved and refrains from Soviet-era songs filled the rain-soaked streets.
"We're free of the occupation!" Lucia Prokorovna said amid bursts of fireworks in Russia's historic naval port of Sevastopol.
"Ukraine was attached to Crimea like a sack of potatoes," the 60-year-old said in reference to the sentimental but what proved to be explosive decision by Soviet leader Nikita Khrushev -- a native Ukrainian -- to present the peninsula to Kiev as a gift in 1954.
Crimea's self-declared premier Sergiy Aksyonov -- recognised by Moscow but rejected as illegitimate by Kiev and most of the world -- hailed the referendum as an "historic moment".
"We're going home. Crimea is going to Russia," he told those gathered on Lenin Square.
- 'Mockery' of democracy -
Not everyone in Crimea was ecstatic with the result.
Some ethnic Ukranians expressed bewilderment at a referendum that presented them with only two choices: to join Russia or go back to a 1992 constitution under which Crimea became a de facto sovereign state.
The status quo or better terms with Kiev were not options -- a reality that along with the massive presence of Russian troops across the region prompted British Foreign Secretary William Hague call the vote a "mockery" of democracy.
Crimea's indigenous Muslim Tatar community -- deported to Central Asia en masse by Stalin -- also largely boycotted the referendum.
One of the greatest uncertainties hanging over Crimea itself is how the economically devastated region that relies on Kiev for subsistence can survive in the span it would take to formally be accepted as a part of Russia.
More nationalist voices in Ukraine -- a culturally splintered nation of 46 million people -- are calling on the authorities to cut off Crimea from basic supplies in effort to get its leaders to reverse course.
"Crimea's access to gas, electricity, water and food staples is in danger -- and Russia will not be able to compensate," said Penta institute analyst Volodymyr Fesenko.