* Kerry, NATO and EU chiefs clash with Russia's Lavrov
* Western diplomats meet Ukraine opposition in Munich
* Moscow hits back, saying West gives Ukraine no choice (Recasts after Ukraine minister and Klitschko spar on panel)
By Stephen Brown and Alexandra Hudson
MUNICH, Feb 1 (Reuters) - The opposing sides of Ukraine's political crisis put their cases to world powers on Saturday, with the opposition buoyed by pledges of support from the West while Ukraine's foreign minister accused Europe of forcing Kiev into a strategic choice.
Meanwhile the United States and Europe, which held private meetings with the opposition, exchanged angry words with Russia, accusing it of exactly the same thing - strong-arming Kiev into an unpopular alliance.
"Nowhere is the fight for a democratic, European future more important today than in Ukraine," U.S. Secretary of State John Kerry said. "The United States and EU stand with the people of Ukraine in that fight."
He added that protesters believed their futures "do not have to lie with one country alone, and certainly not coerced".
Boxer-turned-opposition-leader Vitaly Klitschko told reporters at the annual security meeting in Munich: "I leave the conference stronger because I feel huge support from friends of Ukraine. Everyone is afraid that instability in one of the largest countries in Europe could bring instability to the whole region."
He called for urgent steps to defuse the violence, and said everything now hinged on the behaviour of President Viktor Yanukovich, whose decision two months ago not to sign an association agreement with the European Union triggered fierce anti-government protests centred on Kiev's Maidan square.
Foreign Minister Leonid Kozhara said Ukraine was undoubtedly part of Europe but "not all Ukraine supports the Maidan".
"There are 8 million ethnic Russians living in the country," he said. "Do you think they are happy when European politicians say 'You must make a strategic choice, you must take Ukraine away from Russia and put it somewhere else'?" he asked.
Had Kiev signed the association agreement, it would still have had a collapsing economy, while Russia made an attractive offer, he said. Moscow's $15 billion loan has thrown Ukraine an economic lifeline.
Klitschko sat stony-faced beside Kozhara for the panel debate on Ukraine. He spoke in German and English and got the loudest applause of the whole conference.
"We have to act now before it is too late," he said. "We want to ensure the crisis in the Ukraine is solved because it can trigger a crisis in the whole region."
Russian Foreign Minister Sergei Lavrov, outnumbered in Munich by supporters of Ukraine's overtures to the European Union, said "political choice was preordained for Ukraine" when the Western military alliance offered Kiev a path to membership in 2008. Ukraine demurred, but does cooperate with NATO on international peace missions, such as in Afghanistan.
"Here a choice is being imposed," said Lavrov, accusing some EU politicians of fomenting anti-Yanukovich protests by people who "seize and hold government buildings, attack the police and use racist and anti-Semitic and Nazi slogans".
CHILL ON THE PODIUM
Differences between Russia and the Western allies on Ukraine and Syria, where Moscow backs President Bashar al-Assad, made for a chilly atmosphere on the Munich podium.
Kerry and other Western diplomats put the burden of responsibility for the violence in Ukraine on the government.
"We strongly condemn the violence we have seen, not least the excessive use of force by the security forces," said NATO chief Anders Fogh Rasmussen. "We insist on full respect for the fundamental principle that each and every country has an inherent right to freely choose its alliances."
European Council President Herman Van Rompuy said the EU's offer of an association deal remained on the table, adding: "The future of Ukraine belongs with the European Union."
Yanukovich has signed into law an amnesty for detained demonstrators and repealed anti-protest legislation.
Kozhara also granted Germany's request for an anti-government activist held captive for a week and severely beaten to be allowed to travel to the European Union for treatment.
Activist Dimitri Bulatov, a leader of the protest motorcades called 'Automaidan', reappeared on Thursday with his face badly beaten and with wounds to his hands, saying he had been tortured by his kidnappers. (Additional reporting by Missy Ryan, Adrian Croft and Anna McIntosh; Writing by Stephen Brown; Editing by Tom Heneghan)