For most of the last two years, the big eurozone sovereign crisis trade has been to buy the debt of stronger northern European countries and sell that of their struggling southern peers.

Italian 10-year bonds currently yield 4.9%; 2.7 percentage points more than France. That partly reflects Italy's far-higher level of public debt: 126.1% of GDP in the second quarter of 2012, compared to 91% in France. Italy also faces political uncertainty tied to its elections in 2013.