ROME: Italy's political parties will hold a fourth round of voting on Thursday to elect a new head of state, but with the parties still blocked over a mutually acceptable candidate it appeared likely to be inconclusive.

The race for the prestigious, seven-year role is wide open and neither the centre-right nor the centre-left bloc have enough votes to push through their candidate, meaning some sort of compromise deal will be needed.

Prime Minister Mario Draghi remains a contender for the job, but is not the shoo-in many had predicted, with lawmakers clearly reluctant to back him, partly because they fear any change to the government could trigger early elections.

Centre-right leaders met early on Thursday to thrash out a strategy, but with no cross-party talks scheduled, an immediate deal appeared unlikely.

"I don't think we'll wrap it up today. I think we will do it tomorrow," former Prime Minister Matteo Renzi, who heads the centrist Italia Viva party, told Radio Leopolda.

Three days of secret ballots https://www.reuters.com/world/europe/italian-presidential-elections-shrouded-parliamentary-secrecy-2022-01-13 in parliament have so far failed to elect a new head of state to replace the outgoing President Sergio Mattarella. A fourth round of voting was due to begin at 1000 GMT on Thursday.

Until now, a successful candidate has needed a two-thirds majority to win, but the threshold falls to an absolute majority from Thursday onwards.

Enrico Letta, head of the main centre-left party, the Democratic Party (PD), has warned the centre-right not to try to agree backroom deals with an array of unaffiliated lawmakers to get someone from their camp elected president.

Parties from both blocs are in Draghi's year-old national unity government, but Letta wrote on Twitter that any unilateral move over such an important decision would sink the coalition. "It would be the quickest way to blow everything up," he said.

The centre-right has so far put forward three candidates from its ranks - a former Senate speaker, a former mayor of Milan, and a retired magistrate - but the centre-left swiftly dismissed the trio and called for further talks.

Besides Draghi, other names floated in the media include former lower house speaker Pier Ferdinando Casini, former premier Giuliano Amato and Senate speaker Elisabetta Casellati.

The easiest solution would be for Mattarella to accept a second mandate. He has so far ruled this out, but he topped Wednesday's ballot, winning 125 votes, suggesting many lawmakers are hopeful he might change his mind.