Euro-area leaders granted immediate respite to the stressed bond markets of Spain and Italy, leaving investors looking to the European Central Bank to provide more lasting relief.

By addressing flaws in their bailout programs, moving toward a banking union and trying to break a negative-loop between troubled sovereigns and banks, officials today triggered the biggest rally in Spanish bonds and the euro this year.

Whether the gains are extended may depend on the willingness of ECB policy makers to next week reward political progress with greater crisis-fighting steps of their own. Governments must also avoid their past mistake of declaring victory too soon as investors press them to move faster on binding the 17-nation euro region more closely together.