Italy: Silvio Berlusconi was set to be discharged from hospital Thursday after spending an extra night in care following a bloody weekend attack.

Berlusconi's personal doctor Alberto Zangrillo said Wednesday he ordered the 73-year-old leader to stay another night in hospital because he was in "a state of suffering that is not always easily controlled" by pain medication.

Berlusconi is suffering "persistent pain... and difficulty eating", he said.

Old neck pains that resurfaced after the attack were causing Berlusconi severe headaches.

The attack left Berlusconi with a broken nose, two broken teeth and other facial injuries, but the prime minister will not need plastic surgery, Zangrillo said.

Also Wednesday, police and bodyguards overpowered a 26-year-old man and arrested him at around 2:00 am (0100 GMT) on the seventh floor of the Milan hospital that is treating Berlusconi, police told AFP.

"He was coming out of the lift when bodyguards and police immobilised him immediately," a spokesman said.

The intruder "said he wanted to talk to the prime minister," the spokesman said. "He did not have an aggressive attitude or any weapon or dangerous object on him."

Police said the man had been treated for mental health troubles.

Berlusconi's assailant, Massimo Tartaglia, 42, remains in police custody despite a request from his lawyers to transfer him at least temporarily to a psychiatric hospital.

A judge deemed that Tartaglia, who police have said has a long history of psychiatric problems, was still capable of carrying out a similar act, the ANSA news agency reported.

While Tartaglia claims to have acted alone, investigators are pursuing suspicions that he may have been set up, ANSA said.

Tartaglia, who hurled a model of Milan's gothic cathedral at the prime minister, faces up to five years in jail if convicted of assault.

Doctors have told Berlusconi to avoid stressful public duties for two weeks, and he has called off a trip to the Copenhagen climate summit this week and a Christmas Eve trip to L'Aquila, the Italian city where nearly 300 died in an earthquake in April.

The attack has sparked acrimony within Italy's political class.Analysis: Italy's political divide

On Wednesday the left and right continued a war of words, trading accusations of creating a "climate of hatred" that led to the attack on Berlusconi.

The head of a vast media empire, Berlusconi has targeted prosecutors seeking his conviction on corruption charges, as well the Constitutional Court, which threw out an immunity law that protected him from prosecution while in office.

Last month after a Mafia turncoat alleged he had links with organised crime in the early 1990s, Berlusconi threatened to "strangle the authors of fiction about the Mafia."

Berlusconi, now in his third term as prime minister, is fighting mounting domestic troubles. Allegations about dalliances with other women led his wife Veronica Lario to file for divorce.