Russia has test-fired an intercontinental ballistic missile in a pre-arranged move as tension mounts over Ukraine's Crimea region. Vladimir Putin said there was no need to use military force in Crimea, but it would only be used as a "last resort".
Russia has said it will retaliate if the United States imposed any sanctions over the country's actions in Ukraine, after US Secretary of State John Kerry warned that the US was prepared to take action to "isolate Russia" unless the tension was reduced.
"We will have to respond," foreign ministry spokesman Alexander Lukashevich said in a statement.
"As always in such situations, provoked by rash and irresponsible actions by Washington, we stress: This is not our choice," he added.
Russian president Vladimir Putin said he would only use force in Ukraine as a "last resort" as he defended Russia's actions in Crimea.
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