President Obama warned of “consequences” Wednesday if Ukraine failed to restore calm after a day of violence in the capital, while the State Department announced that it would bar 20 senior members of the country’s government from traveling to the United States.

“We hold the Ukrainian government primarily responsible for making sure that it is dealing with peaceful protestors in an appropriate way,” Obama said. “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 protestors.”

Fiery street clashes that played out on live television Tuesday left at least 25 dead in and around Independence Square in central Kiev. The violence represented a failure of international hopes that President Viktor Yanukovych could settle differences with his political opponents peacefully and that the former Soviet state could begin to address its underlying financial crisis.

The State Department said the 20 officials blocked from receiving U.S. visas were deemed to be complicit in Tuesday’s violence. It did not identify the officials but said they were all civilians.

The administration appeared to struggle Wednesday to condemn the violence in Independence Square while extending a hand to Yanukovych, a leader who has teetered between Western and Russian allegiances.

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Protests first started in Ukraine on Nov. 21, when President Viktor Yanukovych rejected a deal with the European Union and moved closer to Russia. Violence flared back up again Tuesday after the parliament refused to take up the issue of a new constitution.

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In brief remarks shortly after arriving in Toluca, Mexico, for an economic summit, Obama said a majority of Ukrainians see their future in Europe, a quiet reference to the tug of war between Western nations and Russia for influence in the nation of 19 million. He also said the United States expects protesters to remain peaceful.

“There will be consequences if people step over the line,” Obama said. He did not spell out just what that line is, but said the United States is considering its next step in concert with European nations. He added a particular warning that the Ukrainian military should not “step into what should be a set of issues that can be resolved by civilians.”

Secretary of State John F. Kerry appealed to Yanukovych to be a statesman.

“President Yanukovych has the opportunity to make a choice. The choice is between protecting the people that he serves, all of the people, and a choice for a compromise and dialogue versus violence and mayhem,” Kerry said during a diplomatic visit to Paris. “We believe the choice is clear, and we are talking about the possibility of sanctions or other steps with our friends in Europe and elsewhere in order to try to create the environment for compromise.”

French Foreign Minister Laurent Fabius added that he and diplomats from Germany and Poland would travel to Ukraine ahead of an unusual European Union meeting of its 28 member countries on Thursday devoted to Ukraine.

E.U. sanctions could ban targeted Ukrainian officials from traveling in Europe and could freeze their assets there. France, Poland, Germany and others appeared to back sanctions to increase pressure on the government in Kiev.

European Commission President José Manuel Barroso blamed Ukraine’s “political leadership” and said sanctions are likely.

“We therefore expect that targeted measures against those responsible for violence and use of excessive force can be agreed by our member states as a matter of urgency,” Barroso said.

U.S. lawmakers of both parties called for additional sanctions on those found culpable. Those could include more individual travel restrictions or financial penalties imposed by the United States or along with the European Union. The Obama administration is not contemplating broad national sanctions against Ukraine, officials said.

“We’ve made clear that we would consider taking action against individuals who are responsible for acts of violence within Ukraine, and we have a tool kit for doing that that includes sanctions,” White House deputy chief of staff Ben Rhodes told reporters traveling with Obama.

Sen. Robert Menendez (D-N.J.), chairman of the Senate Foreign Relations Committee, blamed Yanukovych for “state-sponsored violence.”

“The actions of President Yanukovych and his government are deplorable, and the time is now to apply sanctions against the Ukrainian government for gross human rights violations,” Menendez said. “I expect the administration, with congressional support, to act swiftly.”

Sens. John McCain (R-Ariz.) and Chris Murphy (D-Conn.) said they are working together on legislation to impose “targeted sanctions” against those who carried out or supported violence, “or who are complicit in the rollback of Ukraine’s democracy.”

The United States has little direct leverage over the Yanukovych government or the protesters, but any sanctions applied by the European Union could have greater bite. Many Ukrainian officials have business or other financial ties in Europe, and they travel there more often than to the United States.

“We have also made clear that Ukraine has a future that is a part of the Atlantic community,” Rhodes said, but “it is not a zero-sum game with Russia.”

David Nakamura in Toluca, Mexico, and Karla Adam in London contributed to this report.