Story highlights Second round of talks between protesters and government ended without deal

Both parties say negotiations will continue as protesters, riot police hold truce

Ukraine's opposition demands resignation of the government and vows to stay in the fight

Ukrainian government demands protesters admit to extremist actions

A second round of talks Thursday between Ukrainian President Viktor Yanukovych and opposition leaders were fruitless, but both parties decided to keep talking.

Ukrainian anti-government protesters observed a truce of several hours with police to give the negotiations room for success.

Hundreds of protesters, who have been clashing with police in the capital, Kiev, since Sunday heard from boxer-turned-opposition-leader Vitaly Klitschko after the talks with Yanukovych.

"He said no to his resignation and cabinet resignation." Klitschko told opposition supporters who want the government to resign and start early elections, among other demands.

"It does not make sense to negotiate with someone who intends to cheat," Klitschko said.

The sharp rhetoric was echoed by the President's press office, which issued a statement after the talks.

"Unfortunately, for the second time, leaders of the opposition refused to declare the statement condemning extremist actions," it said.

The president's statement goes on to say that "negotiations will be continued."

On Wednesday Klitschko told supporters that he would lead them in an "attack" if their demands for snap elections were not met. He accused Yanukovych's government of having the blood of protesters on its hands after four reported deaths in the clashes.

"When we talked about canceling the new laws that make each of us here a criminal, we heard that maybe this can be a point of negotiations," Klitschko said Wednesday. "I will be with the people. If I have to fight, I will fight. If I have to go under bullets, I will. I will stand up for the people, because I want to live in a different country."

He added, amid the chants of supporters: "If tomorrow the President does not make a step forward, we will attack."

Meanwhile, Prime Minister Mykola Azarov declined Thursday to apologize for the violence unfolding during the protests and told CNN's Richard Quest that law enforcement officers acted within the law and did not have firearms.

Police were merely responding to an effort to overthrow the government, Azarov said, adding that Ukraine was not in Russia's pocket.

Thousands of protesters have been braving the freezing cold to voice their anger against the sweeping new anti-protest laws.

Old and young, they have been building makeshift barricades and weapons in the snow as they take on riot police.

Foreign governments voice concern

Washington has condemned the growing violence -- particularly against journalists and peaceful protesters -- and, alongside the European Union, has urged all parties to exercise restraint and find a democratic solution to the political crisis.

The U.S. ambassador to Russia, Michael McFaul, tweeted Wednesday that he was "watching with sadness" the events in Kiev.

The U.S. Embassy in Kiev said in a prepared statement that it has "revoked the visas of several Ukrainians who were linked to the violence" in response to actions taken against protesters in November and December.

"We are considering further action against those responsible for the current violence," it said.

Poland and Germany said their foreign ministers had spoken by phone to their Ukrainian counterpart, Leonid Kozhara, voicing their concern about the escalating violence.

German Chancellor Angela Merkel issued a statement urging the Ukrainian government to hold discussions with the opposition.

"We expect that the Ukrainian government secures its people democratic freedoms, especially to allow for peaceful demonstrations, to protect lives -- and that the use of force does not take place. We are not just concerned but appalled in the way certain laws were pushed through that would put into question such freedoms," she said.

Controversial law

The clashes are an escalation of weeks of largely peaceful public protests prompted by Yanukovych's decision in November to spurn a planned trade deal with the European Union and turn toward Russia instead.

The controversial new protest laws have sparked concerns they could be used to put down demonstrations and deny people the right to free speech.

They include provisions barring people from wearing helmets and masks to rallies, from setting up tents or sound equipment without prior police permission, and from traveling in convoys of more than five vehicles without authorization.

A separate Interior Ministry order allowing riot police to use firearms came into force Tuesday, according to the official Ukrainian legislation website.

Ukraine's Institute of Mass Information, an organization promoting media rights and freedom of speech, said 36 journalists had been injured while reporting on the clashes in recent days.

Ukraine's national union of journalists called on the Interior Ministry on Wednesday to issue an order forbidding police from using violence against journalists.

Ukraine's future ties

In December, despite weeks of protest by anti-government demonstrators, Yanukovych agreed to a deal with Russian President Vladimir Putin for Moscow to buy Ukrainian debt and slash the price Kiev pays for its gas.

The tumult in Ukraine goes to the heart of its future ties with Russia and the rest of Europe. Ukraine is split between pro-European regions in the west and a more Russia-oriented east.

The protests have unfolded since November 21, when Yanukovych changed his stance on the EU trade pact, which had been years in the making.

The demonstrators say an EU agreement would open borders to trade and set the stage for modernization and inclusion. Ukraine's government says the terms needed to be renegotiated to protect Ukrainians better.