U.S. Treasurys are trading at their worst levels relative to German debt in three years as continued signs of recovery in the world’s largest economy foster expectations of an unwinding of monetary stimulus.

The extra yield investors require to hold ten-year Treasurys instead of German Bunds widened to 0.71 percentage point Wednesday, from 0.58 percentage point just a week ago. This is the largest premium demanded since 2010. Treasury yields climbed to a 13-month high of 2.19% Wednesday, while Bunds yielded 1.49%.

Market action underscores the contrast in outlook for monetary policy in the U.S. and the euro zone, where feeble economic activity has bolstered hopes of further rate cuts by the European Central Bank, and even the distant prospect of negative deposit rates, a situation in which investors would essentially be paying the bank to hold their cash.

A willingness to even consider this reflects a shift in the ECB’s stance. In the past the central bank viewed lowering the deposit rate below zero as disruptive given its adverse impact on the functioning of money markets as well as wider savings behavior.

Meanwhile Treasurys have foundered in recent weeks, hampered by comments from Federal Reserve Chairman Ben Bernanke that were interpreted as signaling a tapering off of the bond purchases which have been a crucial aspect of the Fed’s monetary easing program.