80 to 90 per cent of branches closed
The twin strikes, which follow one earlier in July at Intesa Sanpaolo, came as Italian bank executives faced pressure to slash costs and shed assets to repair balance sheets hit in the euro zone debt crisis.
"The heavy participation to the strikes also shows that there is a big distance between staff and top executives," Fabi union leader Lando Maria Sileoni said in a statement.
Workers at Monte Paschi, which has asked for state aid to plug a capital shortfall, are opposed to chief executive Fabrizio Viola's plan to cut 15 per cent of the bank's workforce and close 400 branches out of 3,000.
The more than 4,600 job cuts planned by the Siena-based lender include 2,300 back office personnel and 1,300 employees of units that will be sold.
"Bankers cannot possibly think there is room for their compensations while at the same time jobs and salaries... are put into question," Agostino Megale, Fisac secretary general, said.
Workers at UniCredit, Italy's biggest bank by assets and which is led by chief executive Federico Ghizzoni, are opposed to the suspension of a bonus payment.
Monte Paschi's head of human resources said in an interview with Reuters the bank would start talks with unions early in August with the aim of reaching an agreement in 50 days.
UniCredit said the bonus payment was tied to its business plan to 2015, which envisages a recovery in profitability, greater labour flexibility and a staff rationalization.
"The UniCredit group, notwithstanding a very complex year for the entire financial industry, is available to pay a collective bonus to staff which is coherent with is 2015 business plan," the bank said.
Unions at Intesa Sanpaolo went on strike on July 2 to protest against feared pay cuts after Italy's biggest retail bank put on hold 4,200 planned layoffs because of the government's pension reform.