Italian news reports say a man punched Italian Premier Silvio Berlusconi in the face at a rally in Milan and the leader was whisked away in a car after falling to the ground.

Berlusconi collapsed after being hit and his entourage immediately got him into a car and drove him away, witnesses told a News agency.

Italian police have arrested a man.

State TV showed Berlusconi with blood on his lips as he was lifted to his feet by aides.

A spokesman for Berlusconi says he didn't immediately have any information about the incident, which happened after the premier delivered a long, rousing speech to his conservative supporters Sunday evening.

The Italian Prime Minister has had a difficult year. As well as battling divorce proceedings and months of sleaze allegations, Mr Berlusconi is also besieged on the legal front.

Italy's highest court ruled in October that a law which had given him immunity from all criminal prosecutions while in office was unconstitutional.

The repeal of the law has reactivated two corruption trials, including one involving allegations that he paid a 360,000 bribe to his British former tax lawyer, David Mills, the estranged husband of Cabinet minister Tessa Jowell, to lie for him in court.

Both deny the allegations.