"the success of monetary union anywhere depends on its success everywhere."

Mario Draghi: Stability and prosperity in Monetary Union

Speech by Mr Mario Draghi, President of the European Central Bank, at the University of Helsinki, Helsinki, 

Sovereign debt needs also to act as a safe haven in times of economic stress. It can do so first of all through a strong fiscal governance framework. Secondly, by having some form of backstop for sovereign debt in place. "Over the longer-term",  "it would be natural to reflect further on whether we have done enough in the euro area to preserve at all times the ability to use fiscal policy counter-cyclically. But it is also clear that- this could only take place in the context of a decisive step towards closer Fiscal Union".

http://www.bis.org/review/r141127i.htm