European Central Bank President Mario Draghi vowed on Thursday to take vigorous action if necessary to preserve the euro and prevent a collapse of the eurozone. His comments are his most positive to date. Stock markets jumped up on Thursday following Draghi\'s comments, which raised expectations that the central bank might intervene and help reduce high borrowing costs that are burdening government finances in Europe. \"Within our mandate, the ECB is ready to do whatever it takes to preserve the euro. And believe me it will be enough,\" Draghi told the Global Investment Conference in London, a forum organized by the British government. He said high borrowing costs came within the ECB\'s mandate if they \"hamper the functioning of the monetary policy transmission channels.\" Draghi stressed that \"we have to cope with this financial fragmentation by addressing these issues.\" He also called the euro \"irreversible.\" His remarks suggest that the central bank may act in the near future, possibly by resuming purchases of sovereign bonds on secondary markets or by providing critical eurozone financial rescue funds with more resources. Record Spanish yields Pressure has grown on the ECB to help ease tension on government bond markets, with the yield on Spanish 10-year debt exceeding the 7.0 percent level that is seen as the maximum sustainable borrowing price. Following Draghi\'s comments, the yield on 10-year Spanish bonds dropped to just below 7.0 percent from 7.376 percent on Wednesday, but the level is still considered unsustainable in the long term. Stock markets in Europe and the United States were also given a boost by the ECB head\'s remarks. In afternoon trades on European stock markets, London\'s benchmark FTSE 100 index jumped 1.43 percent, the Paris CAC 40 went up 3.10 percent and Frankfurt\'s DAX 30 1.82 percent. In the US, the Dow opened up 1.79 percent on the news, the S&P 500 rose 1.68 percent and the Nasdaq 1.74 percent.