The survey by pollsters ISPO, published in the Corriere della Sera daily, said 65 percent of those polled thought the introduction of the euro had been more damaging than beneficial for the Italian economy.

Confidence in the European Union stood at 51 percent, the lowest level in many years, Corriere said.

The poll highlights growing concerns over the future of the single currency among Italians as the euro zone's third largest economy struggles with a spreading debt crisis that has pushed its borrowing costs to unsustainable levels.

The technocrat government of Prime Minister Mario Monti, appointed in November, has pushed through a painful austerity budget including tax hikes and spending cuts that are hitting Italians hard, while the economy heads toward recession.

Monti's approval rating rose to 56 percent from 46 percent a month ago, the ISPO survey showed and 60 percent of those interviewed said Italy had had to join the euro and there was no going back. But 31 percent said they would prefer a return to the lira.

Italy, whose-debt-to-GDP ratio is second only to Greece in the euro zone at 120 percent, was among a raft of European countries hit by a mass downgrade from Standard & Poor's on Friday, with its sovereign rating cut by two notches to BBB+.

(Reporting By Silvia Aloisi)