Italian Prime Minister Silvio Berlusconi's approval rating has slipped in the past month while faith in opposition parties inched up ahead of regional elections in March, according to a poll published on Tuesday.

The monthly poll by IPR Marketing published by La Repubblica newspaper suggested the sympathy jump in Berlusconi's popularity was fleeting after a man hurled a statuette in his face after a rally in December, fracturing his nose and teeth.

The survey of 1,000 Italians, conducted in mid-February, showed Berlusconi's approval rating slipping 2 percentage points to 46 percent, after it rose to 48 percent in December and January.

The newspaper did not provide an explanation for the fall, which left Berlusconi's rating well below an October 2008 high of 62 percent.

The poll showed the 73-year-old media mogul continued to polarize public opinion, with the percentage of Italians with little or no faith in Berlusconi reaching its highest ever level at 52 percent. Only 2 percent of Italians were undecided.

The newspaper, controlled by one of Berlusconi's business rivals Carlo de Benedetti, showed faith in the main opposition Democratic Party (PD) rising by 3 percentage points to 40, recovering most of the 4 point loss seen the previous month.

Its partner Italy of Values (IDV), led by firebrand former anti-corruption magistrate Antonio Di Pietro, gained 2 percentage points to 38 percent approval.

Berlusconi's People of Freedom (PDL) party remained stable on 46 percent approval, with its Northern League opposition partner also unchanged on 31 percent.

The Catholic center-right UDC party, which has flirted with regional alliances with the opposition for the March 28-29 polls, was stable on 40 percent approval, the survey said.

Recent measures of voting intentions give Berlusconi's center-right coalition a clear lead over the center-left opposition ahead of the March vote in 13 of Italy's 20 regions.

The center left, shaken by internal divisions and sex scandals in two important regions, controls 11 of the 13 regions where elections will be held and risks losing as many of five or six of these, as high unemployment and a faltering economic recovery have failed to dent the government's popularity.

The IPR poll said 40 percent of Italians polled expressed faith in the government, while 56 percent did not -- levels which have not changed for four months.

(Reporting by Daniel Flynn)