The eurozone’s sovereign debt crisis is the biggest threat facing the global economy, according to the Organization for Economic Co-operation and Development, Reuters reports. The OECD also said that a collapse of the currency zone is now a possibility, and called on the European Central Bank to continue with its extraordinary measures, such as buying government bonds, to defuse the crisis. Separately, rumours emerged in the Italian press that the country was in talks with the International Monetary Fund to obtain $827 billion at a rate of between 4-5 per cent to refinance it debt for the next 18 months. An IMF spokesperson later denied that emergency aid negotiations were ongoing, according to Reuters. U.S. President Barack Obama also said he would put pressure on eurozone leaders to find a bold and comprehensive solution to the crisis, which is emerging as an important issue in the 2012 U.S. election.