Italy presidential battle heads into third day

 Italy's presidential election will go into a fourth and likely decisive round on Saturday more after two more inconclusive votes on Friday, AFP reports.

Under constitutional rules, a fourth round of voting sees the threshold for victory dropped to a simple majority in the 1,009-member electoral college, down from the two thirds required in the opening three rounds.

The fourth vote will take place on Saturday morning with the candidate of Prime Minister Matteo Renzi's ruling Democratic Party (PD) looking well placed to succeed Giorgio Napolitano as head of state.

Renzi on Thursday declared his support for Sergio Mattarella, 73, a Sicilian judge at the constitutional court who is little-known to the general public.

But he is widely respected in politics after a 25-year stint as a parliamentarian and minister with a reputation for integrity.

He is also regarded as a symbol of Italy's battle against organised crime, having entered politics after his elder brother was murdered by the Sicilian mafia.

Mattarella is expected to be able to rely on the backing of most of the 415 PD politicians in the electoral college made up of members of the two houses of parliament - the Senate and the Chamber of Deputies - and 58 representatives of the regions.

With dozens of other lawmakers closely aligned to the ruling party, the former academic will need only limited cross-bench support to get over the winning line.

But Italian presidential elections are nothing if not unpredictable.

In 2013 a revolt within the PD scuppered the favourite Romano Prodi's chances and blocked a decision, forcing Napolitano to agree to start a second mandate which he always insisted he would not finish.

Now 89, the hugely popular figure announced earlier this month that he was too tired to carry on in what is a largely ceremonial role but can become politically significant during times of crisis over the formation of new governments.

Renzi's backing for Mattarella has been interpreted as the end of a temporary alliance the premier forged with disgraced former prime minister Silvio Berlusconi to help drive labour market and electoral reforms through parliament.

Mattarella is seen as an "anti-Berlusconi" figure having severed his ties with the centre right in Italian politics partly because of his distaste for the media tycoon, who still heads the opposition Forza Italia party despite a tax fraud conviction.

Berlusconi was reported Friday to be feeling "betrayed" by Renzi. A popular theory is that the Forza Italia leader was hoping for a sympathetic figure to be installed as president to increase his chances of winning a pardon over his criminal conviction which would allow him to return to parliament.