After 100,000 demonstrators turned out for Sunday's protests, thousands of Ukrainians returned to the streets on Monday, braving temperatures of -10 degrees Celsius (14 degrees Fahrenheit). The clashes that began Sunday mark a spiraling of tensions after two months of demonstrations against President Viktor Yanukovych's refusal to sign a pact for closer integration with the EU.

Former Ukrainian Prime Minister Yulia Tymoshenko, jailed for seven years under Yanukovych on what many consider trumped-up charges, said she would stand with protesters if she could. "Protect Ukraine and do not fear anything," Tymoshenko said in a statement. "Ukraine has no defense other than you. You are heroes."

Monday's protests prompted Yanukovych to make his first public comments on the ongoing violence, calling it a threat to the country.

"I am convinced that such phenomena are a threat not only to the public in Kiev but all of Ukraine," he said in an address broadcast on state TV. "I urge dialogue, compromise and calm in our native land."

"I ask you not to follow those who urge violence, who are seeking to provoke a split between the state and society," Yanukovych added.

Sunday's clashes marked an escalation after two months of protest have brought hundreds of thousands to Kyiv's streets. Officials estimated that Sunday's protests left 100 people injured, including up to 15 journalists, and Ukraine's Interior Ministry added about 100 police officers to that total as the latest rally against Yanukovych turned into street battles.

Very bloody weekend

The Interior Ministry announced that officers had arrested 20 people for "mass rioting." According to the US-funded Ukrainian radio station Radio Svoboda, police also arrested two of its journalists on Monday morning while they filmed the protests and official response.

The US Embassy called on the Ukrainian government to "immediately start negotiations with all sides to resolve the political standoff, address protesters' concerns, and prevent violence from spreading." A spokeswoman for the US National Security Council warned that Washington has considered sanctions against Ukrainian officials, a step urged by the opposition.

Last week, the government introduced legislation that curbs demonstrators' rights. Officials can levy fines and give prison sentences ranging from two to 15 years for public dissent. Punishable offenses include blockading public spaces, entering public buildings en masse, facilitating protests through financial or logistical means, and setting up stages or tents in public spaces.

EU blames Ukraine

EU foreign ministers meeting in Brussels Monday blamed the government's new laws.

"These legislative acts would significantly restrict the Ukrainian citizens' fundamental rights of association, media and the press and seriously curtail the activities of civil society organizations," the ministers said in a joint statement.

On Sunday, protesters arrived in downtown Kyiv wearing masks and pots on their heads, in direct defiance of the new law's restriction on donning anything that obstructs the face. The bill passed swiftly through the Ukrainian parliament on Thursday night. The opposition accused the allies of President Yanukovych, who had favored the law, of skirting the democratic process after they held the vote by show of hands rather than using the procedural electronic system.

Demonstrations began November 21 after Yanukovych shelved an EU Association Agreement he had previously pledged to sign. After Yanukovych's change of heart, Russia gave Ukraine a $15 billion (11 billion euros) aid package including credits and much cheaper gas.

mkg,dr/tj (Reuters, AFP, dpa, AP)