The European Union on Wednesday called for "an immediate end" to the escalating violence in Ukraine, where two people were shot dead in clashes between police and pro-EU protestors.
"I strongly condemn the violent escalation of events in Kiev overnight leading to casualties. The reported deaths of several protesters is a source of extreme worry," said EU foreign policy Catherine Ashton.
"The use of force and resort to violence is not an answer to the political crisis. All acts of violence must come to an immediate end and be swiftly investigated. Those responsible will have to be held to account," she added in a statement.
Two activists were shot dead as Ukrainian police stormed protestors' barricades, the first fatalities since the start of protests over President Viktor Yanukovych's failure to sign a deal for closer ties with the EU.
Saying she was deeply concerned about attacks on journalists and reports of missing persons, Ashton called on the government and the opposition to begin "a genuine dialogue at the highest level".
"The solution needs to meet the aspirations of the Ukrainian people," she said.
Joining a chorus of international protests, NATO Secretary General Anders Fogh Rasmussen also condemned the latest developments in Ukraine, saying "violence can never be the answer to a political crisis".
The foreign ministry of Lithuania, which currently holds the EU presidency, said consultations were taking place in the EU over possible actions.
However, at talks between EU foreign ministers this week, there was no consensus on agreeing sanctions.