Italian Prime Minister Silvio Berlusconi has lost control of Milan and Naples in a local election, indicative, many say, of his flagging popularity, Reuters reported.

Embroiled in multiple corruption charges and a scandal over underage prostitution, the 74-year-old prime minister's defeat resulted in him losing his birthplace, Milan, which is also Italy's financial capital, and the base of his vast business and media empire. Milan has been Berlusconi's powerbase, run for 18 years by conservatives.

The loss in Monday's election also threatens to destabilize his center-right coalition government.

With most votes counted, center-leftist Giuliano Pisapia was set to take Milan's city hall with 55 percent of the vote against 46 percent for Mayor Letizia Moratti.

It's clear we have lost. The only thing to do is to hold our nerve and carry on, Berlusconi told reporters accompanying him on a trip to Romania.

The center-right also suffered a series of other losses. The southern port of Naples, Italy's third largest city, went to the opposition Italy of Values party by a landslide.