Timeline: Battle for Ukraine A controversial election campaign followed by a disputed result plunged Ukraine into a leadership crisis. The two principal players were the rivals for the presidency, pro-Russian Prime Minister Viktor Yanukovych and pro-EU opposition leader Viktor Yushchenko, who emerged as the winner. BBC News charts how the crisis evolved. 23 January : Viktor Yushchenko is sworn in as Ukraine's new president ending the bruising election marathon. In taking the oath of office before parliament, Mr Yushchenko said he would defend the unity of Ukraine. 20 January : Supreme Court rejects Mr Yanukovych's final appeal against the result of the re-run election and declares Mr Yushchenko the winner. Parliament votes to hold Mr Yushchenko's inauguration on 23 January. Mr Yanukovych concedes he has lost the election re-run to Mr Yushchenko, telling supporters in his Donetsk stronghold: "The right of force has won against the force of the law." ...