Russia has questioned the legitimacy of the new Ukrainian authorities, with its prime minister saying it sees the turmoil in Ukraine as a threat to both Russian citizens and Russian interests in Ukraine.
The statement by prime minister Dmitry Medvedev was the strongest criticism yet from Russia, which had backed Ukrainian president Viktor Yanukovych, who fled the capital of Kiev after striking a deal with the opposition.
The Ukrainian parliament has ousted him and set new elections for May, and its new speaker has been named Ukraine's caretaker president.
Medvedev is quoted as saying the new authorities in Ukraine have come to power as a result of "armed mutiny". He lashed out at what he called the EU's recognition of the new authorities as an "aberration of consciousness".
He said Russia would be ready to resume relations with Ukraine once it sees a "normal, modern government based on laws and constitution of Ukraine".
"If you consider Kalashnikov-toting people in black masks who are roaming Kiev to be the government, then it will be hard for us to work with that government," he said.
Medvedev added that Russia's decision to recall its ambassador in Kiev for consultations meant that "there is a threat for our interests, and for life and health of our people in the embassy".