The European Central Bank is poised to announce a plan on Thursday to buy government bonds, resorting to its last big policy tool for breathing life into the flagging euro zone economy and fending off deflation. Market expectations are sky-high for the ECB to unveil a large-scale program of quantitative easing (QE) – printing money to purchase the sovereign bonds – despite opposition from Germany’s Bundesbank and concerns in Berlin that this could allow spendthrift countries to slacken their economic reforms.