Silvio Berlusconi

Italian opposition politicians are demanding Prime Minister Silvio Berlusconi apologize for using an obscenity to refer to anyone who would vote against him in Sunday's election.

During a speech to a group of shopkeepers Tuesday, Mr. Berlusconi used a word regarded by many as an obscenity and by others as an insult.

He said using such language was rough but effective.

The remark came a day after Mr. Berlusconi traded insults in a political debate with his chief political rival, center-left leader Romano Prodi.

Both candidates assailed the other's fiscal policies, with Mr. Berlusconi calling Prodi a "useful idiot" and Prodi saying the prime minister is like a "drunkard clinging to a lamppost."

Voters go to the polls Sunday and Monday to choose a new government. Polls show many of the voters are undecided.