Security forces have pulled back from a protest camp around a central square in Ukraine's capital after clashes between police and pro-European Union demonstrators.
Scuffles between the two groups took place early Wednesday inside Kyiv's city hall, hours after security agents stormed a protest encampment in Kyiv's Independence Square and ripped down a tent city erected by the demonstrators.
Ukrainian President Viktor Yanukovych later vowed not to use force against the protesters and called on the opposition to meet for talks.
The opposition has repeatedly said it would not consider any negotiations until the president dismissed the government, released jailed protesters and punished riot police responsible for violence against demonstrators.
Mr. Yanukovych's offer follows meetings with U.S. Assistant Secretary of State Victoria and European Union foreign policy chief Catherine Ashton who were in Kyiv as part of a push to find a solution to the crisis.
Nuland, who spoke to protesters in Kyiv's Independence Square Wednesday, said she complained to Ukrainian President Viktor Yanukovych about the police use of force.
"I made it absolutely clear to him that what happened last night, what has been happening in security terms here is absolutely impermissible in a European state, in a democratic state."
The protests began in late November, after the Ukrainian president backed away from a long-anticipated trade deal with the European Union, in favor of repairing and improving economic and political ties with Russia.
On Wednesday Ukraine's Prime Minister Mykola Azarov said Ukraine is requesting $27.5 billion in financial assistance from the European Union before it signs an association agreement with the 28-nation bloc.
Mr. Azarov said Ukraine is inviting the European Commission to consider under what conditions Ukraine's industry and economy will work.
On Tuesday, Ukrainian President Viktor Yanukovych met with three former Ukrainian presidents, launching so-called round table talks reportedly aimed at the same objective.
In a nationally televised address following his meeting with his predecessors, Mr. Yanukovych called for the release of protesters arrested after a violent police crackdown November 30. He said good relations with both Russia and the European Union are necessary to protect the country's interests.
Moscow is seeking to form a trade bloc of former Soviet republics and satellite countries to rival the European Union, and has in recent months exerted strong economic pressure on its impoverished neighbor to scuttle the EU deal.
Earlier this year, it imposed restrictions on goods from Ukraine, cutting Ukrainian exports by 25 percent and dragging the country into recession.
Russia is Ukraine's largest foreign investor, trading partner and chief natural gas supplier. Moscow is reported to be dangling a deal with Ukraine that includes a $9 billion annual discount on gas pipeline shipments.
Analysts say Kyiv, which has also secured recent investment deals with China, still needs about $18 billion in outside help to pay government debt and meet energy payments to Russia by early 2014.