Little by little Italy’s biggest lender, UniCredit, is making headway with plans to shore up its balance sheet and become a stabilising influence at home and in the eurozone.

Italian banks, however, can't each repair themselves in isolation. Events in Siena could torpedo efforts in Milan, because Banca Monte dei Paschi di Siena, Italy's third-biggest bank and its most troubled, may struggle to fulfill its own capital raising and restructuring promise.