Unlikely firebrand Arseniy Yatsenyuk could be Ukraine's PM-in-waiting

Ukraine's Arseniy Yatsenyuk, an opposition leader who has been offered the post of government chief by President Viktor Yanukovych, is a pro-EU former foreign minister who has taken a hands-on role in the protests.

The bespectacled 39-year-old has said he is not accepting or rejecting the proposed compromise and vowed to press ahead with demonstrations until all the opposition's demands are met.

"We're finishing what we started. The people decide our leaders, not you," he told Yanukovych in a message on Twitter.

The former lawyer does not have the image of a tough politician and his support among the most militant wing of the protesters is uncertain. But he has taken an increasingly stubborn line in booming speeches on Independence Square in Kiev, the epicentre of the protest movement.

The Ukrainian news weekly Focus said Yatsenyuk had been trying to shed his image of an "intellectual banker" and had been using the daily rallies as a sort of "primary" election for the role of chief opposition leader.

He is also seen by some as a rival as much as ally of fellow opposition leader and former world boxing champion Vitali Klitschko, who currently enjoys greater popularity among potential voters.