KIEV - Ukrainian President Viktor Yanukovych on Thursday unexpectedly took sick leave from work, stepping aside from a crisis that still has no end in sight after lawmakers failed to find consensus on an amnesty law.Yanukovych’s falling sick with an acute respiratory infection is the latest twist in a crisis that has already seen him accept the resignation of the prime minister in a bid to placate protesters.The sudden announcement in Kiev came after the pro-EU opposition vowed further protests in the ex-Soviet country’s worst political crisis since its 1991 independence.The outcome of the crisis remained unclear, with thousands of demonstrators still occupying Kiev’s Independence Square, key streets and municipal buildings in the centre of Kiev.International concern has grown, with Russian President Vladimir Putin urging the European Union not to meddle in the crisis but Western states under pressure from protesters to consider sanctions against Ukrainian officials.The protests started in November as a push for EU integration after Yanukovych under Russian pressure ditched a deal for closer integration with the bloc, but have now become an all-out drive to unseat the president who until now has defiantly refused to budge.“The president is on sick leave,” Yanukovych’s office said in a statement, without saying how long the leave would be for.Citing deputy head of the State Directorate for Medical Affairs, Olexander Orda, the statement said Yanukovych had gone down with an “acute respiratory infection accompanied by an elevated temperature.”While many Kievans have fallen sick in recent days amid frigid temperatures that have plunged to minus 20 degrees Celsius (-4 degrees Fahrenheit), the sick leave with allow Yanukovych a break from increasingly frenzied negotiations to end the crisis. The parliament with backing from the ruling Regions Party late Wednesday passed a bill that would amnesty arrested protesters. But the opposition rejected its conditions and refrained from voting.In an extremely rare move, Yanukovych personally visited parliament and threatened early parliamentary elections if the Regions Party did not support the bill. According to unconfirmed Ukrainian media reports, some 40 Regions Party MPs were ready to side with the opposition.Yanukovych has granted several concessions to protesters, including accepting the resignation of Prime Minister Mykola Azarov and allowing the annulment of anti-protest laws. But the protest movement wants early elections that could replace the head of state.The opposition did not vote for the amnesty bill as it is unhappy that the law is conditional on protesters vacating buildings they have occupied in Kiev.A total of 232 deputies voted for the bill and 11 against, but 173 MPs present in the parliament did not vote in a session which ended in chaos at 11:00 pm (2100 GMT).The opposition is furious with the wording of the bill as the amnesty is conditional on protesters leaving occupied streets and buildings 15 days after it comes into force.“Such actions must be finished no later than 15 days after the law comes into force,” said the text of the bill published on parliament’s website Thursday.Protesters will have to leave all occupied administrative buildings in Kiev and across Ukraine as well as the flashpoint Grushevsky Street in Kiev where three activists were shot dead in clashes with police last week.But it appears they will be allowed to stay on in the protest hub of Independence Square (known as the Maidan) which is not mentioned.Underlining the gravity of the crisis, Ukraine’s first post-independence president Leonid Kravchuk on Wednesday warned that the country was “on the brink of civil war”.Svoboda (Freedom) party leader Oleg Tyagnybok said that parliament had essentially adopted a law about “hostages” as the dozens arrested during the crisis would now be held until buildings are freed.“The authorities have now admitted they take hostages like terrorists do, so that they can then barter over them,” he was quoted as saying. “Don’t believe that the opposition will give up the Maidan,” he said.The UDAR (Punch) party leader and world boxing champion Vitali Klitschko warned: “Instead of lowering the temperature in society, this is going to raise it.”Dozens of activists have been arrested since clashes broke out January 19, both in Kiev and in the provinces, where activists have stormed regional administration buildings.In a move that is likely to complicate matters further, Putin said on Wednesday that Moscow would wait until a new government is formed in Ukraine before it considers releasing a crucial $15-billion bailout package for Kiev in full.Russia released the first $3 billion tranche late last year for the deeply troubled Ukrainian economy.Putin on Wednesday discussed the crisis with German Chancellor Angela Merkel, the Kremlin said, stressing that “any outside interference is unacceptable.” Merkel for her part told Putin to push for a “constructive dialogue” to defuse the crisis in Ukraine, her office said.