Only one Italian bank has so far expressed interest in a government-sponsored bond purchase scheme to boost banks' capital, Prime Minister Silvio Berlusconi said on Sunday, without naming the bank.

Under the scheme announced last week, banks would issue bonds that the government would buy and use the proceeds to shore up their capital.

The securities -- known as Tremonti bonds, after Italian Economy Minister Giulio Tremonti -- will have an annual yield of between 7.5 percent and 8.5 percent for the first few years before gradually increasing.

Berlusconi rejected the idea that any banks which adhere to the scheme would likely have financial difficulties, saying the Tremonti bonds were aimed at boosting capital so banks could provide loans.

Berlusconi said Italy's banks were healthier than their peers abroad and also didn't get wrapped up in toxic assets.

Our banks are the least touched (by the global crisis). The little which regards us relates to those that made acquisitions in Eastern Europe, Berlusconi said.

So far, there hasn't been any problem with capitalization and toxic assets don't relate to us.

UniCredit , Italy's second-biggest bank by market value, is the biggest lender in emerging Europe.

Asked later by reporters whether UniCredit was concerned about the situation, generally, Berlusconi said: (Chief Executive Alessandro) Profumo doesn't seem worried to me.

(Reporting by Paolo Biondi; Editing by Dominic Evans)