He has never been elected to parliament, or served in an Italian government, but Matteo Renzi could be asked to form the country’s next government this weekend.

It’s predicted the Mayor of Florence and leader of the centre-left Democratic Party could be named Italy’s youngest PM by Saturday evening and sworn into office early next week.

President Giorgio Napolitano opened consultations in Rome with other political leaders on Friday afternoon. The heads of the anti-establishment Five Star Movement – which gained a quarter of the vote in last year’s election – and the Northern League refused to take part.

But the current acting leader of the Forza Italia party Silvio Berlusconi, who says he is the last elected prime minister, did join in the consultations.

It’s the first time the former prime minister has met with the president since he was convicted of tax fraud.

The outgoing PM Enrico Letta formally handed in his resignation to the president on Friday.

Opinion polls suggest the majority of Italians disapprove of Renzi taking over without an election.

The fall of the government coincided with Moody’s investor services lifting Italy’s sovereign rating from negative to stable.

Even so the economy, which is one of the world’s slowest growing in the last two years, will be one of the 39-year-old Renzi’s biggest challenges.