Ukraine's presidency said on Friday a deal had been reached at all-night talks on resolving the country's crisis after 75 people were killed in two days of the worst violence since Soviet times.
But the opposition did not immediately confirm agreement had been reached and diplomatic sources described the talks brokered by three European Union ministers as "very difficult."
Talks between opposition leaders and the embattled Ukrainian president continued early Friday as a shaky peace reigned in the protest camps in downtown Kiev.
President Viktor Yanukovych, who was still engaged in talks with opposition leaders and foreign officials, was "going to make concessions in order to restore peace," Interfax Ukraine quoted his spokeswoman Anna German as saying.
Support for the president appeared to be weakening, as reports said the army's deputy chief of staff, Yury Dumansky, was resigning in "disagreement with the politics of pulling the armed forces into an internal civil conflict."
Late on Thursday, the Ukrainian parliament passed a measure that would prohibit an "anti-terrorist operation" threatened by Yanukovych to restore order, and called for all Interior Ministry troops to return to their bases.
But it was unclear how binding the move would be, as the mechanism for carrying it out would have to be developed by the president's office and the Interior Ministry.
On Friday morning, several thousand protesters milled around Independence Square, known as the Maidan, which earlier this week was rocked by street battles between protesters.
The day before European Union foreign ministers agreed to impose sanctions on Ukraine, including visa bans, asset freezes and restrictions on the export of anti-riot equipment, ministers and officials said as the country suffers through the bloodiest hours of its post-Soviet history.
The development comes after fighting broke out in central Kiev Thursday morning, leaving dozens of people dead and shattering a brief truce declared by Yanukovich, as the Russian-backed leader met with European ministers demanding he compromise with pro-EU opponents. The United States had stepped up pressure on Wednesday by imposing travel bans on 20 senior Ukrainian officials.
Vice President Joe Biden called Yanukovich Thursday, urging him “to immediately pull back all security forces” and reaffirming that the U.S. is “prepared to sanction those officials responsible for the violence,” according to a readout from the White House.
MORE: Latest updates @ajamlive | Continuing coverage of Ukraine protests
Ukraine’s Health Ministry said that at least 75 people had been confirmed dead as a result of clashes this week — 26 on Feb. 18 and 19 and at least 49 killed on Feb. 20. On Friday morning, the Associated Press reported the death toll was at least 101.
It is the worst violence since Ukraine emerged after the fall Soviet Union 22 years ago.
A Ukrainian presidential statement said dozens of police were among those killed or wounded.
Many of the deaths came during an eruption of violence just hours after the country's embattled president and opposition leaders demanding his resignation called for a truce and negotiations to try to resolve Ukraine's political crisis.
It's unclear who sparked the early morning violence on Thursday, but the Ukrainian Interior Ministry said that police used live munitions in self-defense.
"For the purpose of preserving the lives and well-being of law enforcement officials, a decision was taken ... to use weapons in self defense," the interior ministry said, adding that its staff "have the right to use firearms" if their lives or well-being are threatened.
Riot police were captured on video shooting from a rooftop at demonstrators in the plaza, known as the Maidan or "Euro-Maidan." Protesters hurled petrol bombs and paving stones to drive the security forces off a corner of the square the police had captured in battles that began two days earlier.
Andy Hunder, director of the London-based Ukrainian Institute, told Al Jazeera that what is being seen in Ukraine is a "president who has cornered himself and doesn't see a way out."
"This is a war of a president against his own people. Yanukovich has decided to turn on the people," Hunder said.
Later on Thursday, an opposition spokesman told Al Jazeera that the Ukrainian parliament agreed to take government forces out of Kiev, in an apparent stand down.
Sviatoslav Yurash, spokesman of the Euromaidan Activists Movement, also indicated that parliament had agreed to ban the use of firearms against protesters.
Meanwhile, Ukraine's Interior Ministry also said Thursday that 67 police troops had been captured by protesters in Kiev.
Video footage on Ukrainian television showed protesters leading some of the captured policemen around the sprawling protest camp. One opposition lawmaker said the police are being held in Kiev's city hall, which is being occupied by protesters.
The scene at Independence Square appeared relatively calmer Thursday afternoon, Al Jazeera's Jennifer Glasse reported, adding that protesters had re-taken the bulk of the square, a few hundred yards from where the president was meeting the EU delegation.
The lobby of the Ukraine Hotel in Kiev has been turned into a makeshift hospital, with doctors and medics operating on wounded people, Glasse reported on Thursday, adding that there were about a dozen dead bodies also in that lobby.
Russia's Foreign Ministry described the violence as an attempted coup and even used the phrase "brown revolution," an allusion to the Nazi rise to power in Germany in 1933. The ministry said Russia would use "all our influence to restore peace and calm."
Russian President Vladimir Putin spoke with German Chancellor Angela Merkel and British Prime Minister David Cameron on Thursday and expressed "utmost concern" over the sharp escalation of violence in Ukraine, Reuters reported.
Neither side had appeared willing to compromise, with the opposition insisting on Yanukovich's resignation and an early election and the president apparently prepared to fight until the end.
Clashes this week have been the deadliest since protests started in November after Yanukovich shelved an association agreement with the EU in favor of closer ties with Russia. Russia then announced a $15 billion bailout for Ukraine, whose economy is in tatters.
Although the initial weeks of protests were determinedly peaceful, radicals helped drive an outburst of clashes with police in January in which at least three people died.
In another development, Ukranian skier Bogdana Matsotska withdrew from the Winter Olympics in Sochi, Russia to protest the deaths of protesters in her country.
Matsotska told The Associated Press: "I don't want to participate when in my country people die." The 24-year-old skier has refused to ski in Friday's slalom, her third and best event at the Sochi Olympics.
Matsotska also said Ukraine President Yanukovich "has to be jailed, and for a long time ... for all the lives that he took," adding, "I hope that I will be heard by the world."
Al Jazeera and wire services