TOLUCA, Mexico - 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 also 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.
"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 alongside Mexican President Enrique Pena Nieto.
During talks, Obama and Canadian Prime Minister Stephen Harper "strongly condemned" the violence, the White House said in a statement.
If the government and the opposition implement a truce announced by both sides, it would be a "welcome step forward," it added.
Harper and Obama also vowed to work closely with European allies on additional measures as they assess the situation.
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.
"And that includes making sure the Ukrainian military does not step into what should be a set of issues that can be resolved by civilians."
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 President Viktor Yanukovych rejected an EU pact in favor of closer ties with former master Moscow.
US sanctions warning
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."
US Senator Robert Menendez, chairman of the Senate foreign relations committee, said "the time is now to apply sanctions against the Ukrainian government for gross human rights violations."
Obama said the United States would continue to engage with all sides in the dispute but that he believes "a large majority of Ukrainians are interested in an integration with Europe."
In Washington, a US diplomat told several 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.
"The Department of Defense is encouraged that the Ukrainian armed forces have not been brought into this crisis," spokesman Colonel Steven Warren told reporters.
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.
On Tuesday, US Vice President Joe Biden called Yanukovych, telling him that security forces that stormed a protest camp on Kiev's Independence Square should withdraw and that the government "bears special responsibility to de-escalate the situation," the White House said.