Tensions had soared after Russia said Monday that it was ready to resume providing the loans that Yanukovych's government needs to keep Ukraine's ailing economy afloat.
This raised fears among the opposition that Yanukovych had made a deal with Moscow to stand firm against the protesters and would choose a Russian-leaning loyalist to be his new prime minister.
The protests began in late November after Yanukovych turned away from a long-anticipated deal with the European Union in exchange for a $15 billion bailout from Russia.
The political maneuvering continued, however, with both Moscow and the West eager to gain influence over this former Soviet republic.
Until Monday, the government and the opposition had appeared to be making some progress toward resolving the political crisis peacefully.
In exchange for the release of scores of jailed activists, protesters on Sunday vacated a government building that they had occupied since Dec. 1.
Russia also may have wanted to see Kiev remain calm through the Winter Olympics in Sochi, so as not to distract from President Vladimir Putin's games.