A police officer uses shields as cover while he aims a shotgun in clashes with protesters. At least two protesters were shot dead in recent clashes. Efrem Lukatsky/AP

Riot police gathering on Jan. 22 in Kiev. They attempted to storm the protesters’ barricades. Anatolii Boiko/AFP/Getty Images

A protester gestures using the arms of a broken mannequin during clashes in Kiev. Sergei Grits/AP

Anti-government protesters carry tires through a barricade of burning debris Jan. 25, 2014, as the standoff in Kiev continues. Volodymyr Shuvayev/AFP/Getty Images

Men carry a casket containing the body of Mikhail Zhiznevsky, 25, an anti-government protester who was killed in clashes with police, through the streets of downtown Kiev after a service in his honor. Brendan Hoffman/Getty Images

Protesters warm themselves at a fire behind a barricade during anti-government protests in Kiev, Jan. 27, 2014. Sergey Dolzhenko/EPA

Ukrainian protesters seized a government ministry in Kiev and besieged several governors' offices in western regions Friday, raising the pressure on the country's Russia-leaning government. But President Viktor Yanukovich showed little willingness to negotiate, promoting his hawkish top aide to his chief-of-staff.

The seizures could complicate talks between opposition leaders and Yanukovich, who has demanded the demonstrators leave other administrative buildings in the capital that have been occupied for nearly two months. The opposition wants Yanukovich to resign in favor of a new election.

Protests have gripped Ukraine since November, when Yanukovich rejected a trade deal with the European Union to pursue closer ties with Russia. Many Ukrainians fear that the country's hard-won independence will be crippled if it moves back too tightly into Russia's orbit.

Yanukovich appeared in no mood for compromise Friday, promoting Andriy Kluyev, whom the opposition holds responsible for violence against protesters, to be his chief-of-staff.

Some opposition leaders expressed hope for negotiations after meeting with Yanukovich for several hours late Thursday, telling crowds that Yanukovich had promised to stop detaining protesters and to release dozens already in custody. They urged the protesters to maintain a shaky truce that has followed violent street battles in Kiev so as to avoid further bloodshed.

But opposition leaders were booed by some demonstrators eager to resume clashes with police.

The truce largely held Friday, but early in the day protesters broke into the downtown Ministry of Agricultural Policy, meeting no resistance. The demonstrators let ministry workers take their possessions but wouldn't let them work.

"We need to keep people warm in the frost," explained protester Andriy Moiseenko, referring to temperatures that dipped to -4 Fahrenheit overnight. "We cannot have people sleeping in tents all the time."

As opposition leader Oleh Tyahnybok called for calm Thursday evening, the 24-hour truce set on Wednesday had already expired without the protesters’ demands being met. The opposition has demanded that the president dismiss the government, call early elections and scrap harsh anti-protest legislation that triggered violence at a demonstration on Sunday.

Despite Tyahnybok’s request, other opposition leaders offered mixed reports on the outcome of the meeting, with opposition politician and former boxing champion Vitali Klitschko saying negotiations had achieved little success.

On Wednesday, Klitschko said Ukrainian protesters would go "on the attack" if Yanukovich did not swiftly offer concessions since people are becoming impatient.

At the barricades Friday outside a government district in Kiev — where fires had raged and rocks had flown for days — dozens of middle-aged women approached police lines chanting, "You are our children!" and "No more mothers' tears!"

One of them, 48-year-old Oksana Tikhomirova, wept as she urged riot police to stop the violence.

"All of these are our children. Both ... the protesters and the riot police are sons of Ukraine," she said. "I have seen people killed and maimed and we must stop that. The violence must stop."

Policemen listened calmly and did not react.

Interior Minister Vitali Zakharchenko issued a statement guaranteeing that police would not take action against the large protest camp on Independence Square, known as the Maidan. He also called on the police to exercise calm and not react to provocations.

The developments came as hundreds of enraged protesters in several regions in western Ukraine, where Yanukovich has little support, seized government offices and forced one governor loyal to Yanukovich to resign.

In Lviv, 280 miles west of Kiev, occupying protesters prevented employees from entering the building after forcing the governor, a Yanukovich appointee, to resign. The governor, Oleh Salo, later retracted his signature, saying he was coerced.

Protesters also retained control of offices in at least two other western cities but suffered a setback in Cherkasy, 90 miles southeast of Kiev, where police barricaded the governor's building from the inside and prevented them from taking control Friday. Police reinforcements arrived later, dispersing the protesters and arresting several dozen.