US President Barack Obama urged Ukraine's government Wednesday to refrain from using violence against peaceful protesters, warning of "consequences" if any further abuses take place.
Obama made his remarks during a visit to Mexico as the European Union scheduled urgent talks to mull sanctions in the wake of clashes between police and anti-government protesters in Kiev that left at least 26 people dead.
The Obama administration placed 20 top Ukrainian officials on a visa blacklist as it threatened to take punitive sanctions against individuals responsible for the violence.
Ukraine's embattled President Viktor Yanukovych announced a truce with the opposition, which Obama said would be a welcome step toward dialogue if implemented.
"We hold the Ukrainian government primarily responsible for making sure that it is dealing with peaceful protesters in an appropriate way, that the Ukrainian people are able to assemble and speak freely about their interests without fear of repression," Obama said.
"I want to be very clear as we work through these next several days in Ukraine that we're going to be watching closely and we expect the Ukrainian government to show restraint, to not resort to violence in dealing with peaceful protesters," he said before talks with Mexican President Enrique Pena Nieto.
Speaking later at a press conference alongside Pena Nieto and Canadian Prime Minister Stephen Harper at the end of a North American summit, Obama urged Yanukovych to withdraw riot police and called on the army to remain on the sidelines.
He also appealed for "progress" on the formation of a multi-party technical government and adopt reforms needed for free and fair elections next year.
"My hope is that at this point a truce may hold," Obama said.
"My government and Vice President (Joe) Biden and I personally have expressed to President Yanukovych the need for him to recognize the spirit of the Ukrainian people and work with that, as opposed to trying to repress them," the US leader said.
While helmeted demonstrators were locked in a tense standoff with riot police across burning barricades, Obama said the United States also expected protesters to remain peaceful.
"We'll be monitoring very closely the situation, recognizing that with our European partners and the international community, there will be consequences if people step over the line," the US leader said.
The crackdown on anti-government protests by security forces on Tuesday triggered a storm of international condemnation, with the 28-nation EU bloc convening urgent talks for Thursday.
The unrest was the deadliest since protests erupted in November after Yanukovych rejected an EU pact in favor of closer ties with former master Moscow.
Obama acknowledged his "disagreements" with Russian President Vladimir Putin over Ukraine and the conflict in Syria but that he did not see this as "some Cold War chessboard in which we are in competition with Russia."
US sanctions warning
In Washington, US senators John McCain and Chris Murphy, who visited Kiev in December, said in a joint statement that they have begun work on legislation to apply "targeted sanctions."
The punitive measures would apply to "government officials and other persons who have committed, ordered or materially supported acts of violence against peaceful citizens in Ukraine, or who are complicit in the rollback of Ukraine's democracy."
A US diplomat told reporters that the United States would deny visas to about 20 Ukrainian officials "considered responsible for, complicit in or responsible for ordering or otherwise directing human rights abuses related to political repression in Ukraine."
The diplomat declined to name the Ukrainian officials concerned.
The Pentagon for its part called on Ukraine's army to stay out of the conflict, warning that it would have consequences on defense ties.
Yanukovych replaced his army chief, Volodymyr Zamana, without providing an explanation.
Zamana is a powerful figure lauded by the opposition for refusing to back the use of force against those who had come out on the street.