Ukraine's president has announced early elections and promised a coalition government.

The Ukrainian presidency has said it has negotiated a deal intended to end violent battles between police and protesters that have killed scores and injured hundreds of people, but European mediators involved in the talks would not confirm a breakthrough.

There are reports a political deal to end the bloodshed in Ukraine has been reached following marathon crisis talks.

Ukrainian opposition leaders issued a stark ultimatum to President Viktor Yanukovych to call early elections within 24 hours or face more popular rage.

At least three people have been killed during clashes between protesters and police in the Ukrainian capital.