The EU says it is putting on hold work on a key trade agreement with Ukraine, saying the government's arguments have "no grounds in reality". Protesters have taken to the streets in support of the agreement, which was rejected by the government.
US Senator John McCain is in Ukraine to meet members of the opposition and government as efforts to mediate the political crisis in the country continue.
Senator McCain said he was clear that he saw the future of Ukraine inside Europe.
Further protests have been called by both sides tomorrow. Today tens of thousands attended rival rallies in the centre of Kiev.
There is an urgent need for de-escalation in Ukraine as President Yanukovich tries to calm a country bitterly divided over years of history.
Ukraine's political and economic landscape is stuck between old Soviet masters in Russia and the democratising ideals offered by the EU.