Ukraine's President Viktor Yanukovych says he has agreed a truce with opposition leaders, after at least 26 people died in clashes this week.
In a statement, he said "negotiations" would now start to end the bloodshed of the last two days.
Opposition leader Arseniy Yatsenyuk confirmed this, saying there would be no new police attempts to storm the main protest site, the Maidan, in Kiev.
Fires are continuing to burn around the Maidan, but no violence is reported.
Most of the victims died during the clashes near the parliament building in the capital and later police attempts to clear the Maidan on Tuesday - making it the bloodiest day since the unrest erupted in late November.
Thursday has been declared a day of mourning for the dead.
In other developments:
- President Yanukovych sacked the armed forces head, Col Gen Volodymyr Zamana, replacing him with the navy commander, Adm Yuriy Ilyin. No reason was given for the dismissal
- US President Barack Obama warned there "will be consequences" for anyone who steps over the line in Ukraine - including the military intervening in a situation that civilians should resolve. He also expressed hopes that the truce "may hold"
- Meanwhile, the US state department said it had imposed visa bans on 20 members of Ukraine' government believed to be responsible for the violence against protesters
- Russia characterised the violence as an "attempted coup" by extremists
- Foreign ministers from France, Germany and Poland are to hold talks in Kiev later on Thursday before an EU meeting in Brussels to decide whether to impose sanctions against Ukraine
The announcement of the truce came late on Wednesday after Mr Yanukovych met members of a crisis group, which included Ukraine's three main opposition leaders, the parliamentary speaker and top officials from the presidential administration.
The statement on the presidential website said that it was agreed to "start negotiations aimed at stopping the bloodshed, stabilising the situation in the country and achieving social peace".
It did not give details of what the truce would entail or how it would be implemented.
The main opposition leaders present at the talks were Mr Yatsenyuk and also boxer-turned-politician Vitali Klitschko and far-right party leader Oleh Tyahnybok.
"The storming of the Maidan (Independence Square) which the authorities had planned today will not take place," Mr Yatsenyuk said in a statement on his Fatherland party.
"A truce has been declared. The main thing is to protect human life," he added.
The media wing of Vitali Klitschko's Udar party said the next round of negotiations with President Yanukovych would resume on Thursday.
But a BBC correspondent in Kiev, Daniel Sandford, has urged caution, pointing out that none of the hardcore protesters have so far attended talks with the president.
The news came after the most intense violence in Ukraine's three-month crisis turned Kiev into a battle zone between anti-government protesters and riot police.
The protests first erupted when President Yanukovych rejected a landmark association and trade deal with the EU in favour of closer ties with Russia.
Since then, the protests spread across Ukraine, with the main demand of snap presidential and parliamentary elections.
Clashes erupted on Tuesday morning as protesters marched to the parliament building, pressing for constitutional changes to limit what they described as "dictatorial" powers of President Yanukovych.
The violence escalated when the riot police later tried to wrest control of the Maidan in Kiev's Independence Square, which has been in the hands of protesters for several months.
While the violence temporarily subsided on Wednesday, there were still periodic clashes, and protesters seized the central post office adjacent to the Maidan.
The unrest has also spread outside of Kiev, with protesters seizing regional administrative and police buildings in the western cities of Lviv, Ternopil and Ivano-Frankivsk.
A government office was seized in the northern city of Zhytomyr, and there were clashes in Vinnytsia, central Ukraine, and Poltava, to the east of Kiev.
A woman was also reportedly shot dead during an attempt to storm a building belonging to the security services in Khmelnytskyy, west of the capital.
On Wednesday, Ukraine's state security service announced it was preparing a nationwide "anti-terrorist" campaign to deal with a growing "extremist threat". There was also a suggestion the armed forces could be deployed for the first time.