ROME: Paolo Gentiloni was named as Italy's new prime minister on Sunday, filling a void left by close ally Matteo Renzi's resignation after a crushing referendum defeat.
Gentiloni, 62, served as foreign minister under Renzi. He was asked by President Sergio Mattarella to form a new centre-left government that will guide Italy to elections due by February 2018.
Opposition parties demanded an immediate vote, claiming the new government would be a puppet administration with Renzi pulling the strings from behind the scenes.
"Gentiloni is Renzi's avatar," said Luigi Di Maio, one of the leaders of the populist Five Star Movement.
The softly-spoken, grey-suited Gentiloni will mark a distinct change in style from the ebullient, hyper-active Renzi.
But he is expected to make only minor changes to his former boss's team before presenting them to parliament for approval on Wednesday.
In a brief statement after meeting Mattarella, he said there was an "urgent need for a fully functioning government" to address several pressing issues.
Chief among those is a looming crisis in the troubled banking sector and ongoing relief efforts after deadly earthquakes between August and October.
The board of Italian bank Monte dei Paschi di Siena (BMPS) was Sunday locked in crisis talks that will determine whether the world's oldest bank requires a state-funded and politically complicated rescue.
Mattarella turned to Gentiloni after opposition parties rebuffed overtures about a possible national unity government. The president rejected the opposition's demands for an election.
"Not by choice but out of a sense of responsibility I will be forming a government based on the outgoing majority," Gentiloni said.
Renzi, who had been in power for two years and 10 months, resigned last week after voters overwhelmingly rejected a package of constitutional reforms.
Five Star, which has led calls for immediate elections, said it would boycott Wednesday's vote because the new government would have no legitimacy.
"This government is not even worthy of a vote against it," said Giulia Grillo, head of the Five Star group in the Senate.
Renzi meanwhile admitted on his Facebook page that he had found it a wrench to leave office.
"It was painful to pack the cartons yesterday evening, I'm not ashamed to say: I'm not a robot," the 41-year-old wrote.
"Only those who try to change things can help a country as beautiful and difficult as Italy."
Five Star, Italy's biggest opposition party, and the far-right Northern League are demanding a vote as early as possible.
But Mattarella, who enjoys extensive executive powers during government crises, has ruled that the current electoral laws must be revised first.
Theoretically that could happen quickly but the process of harmonising the rules governing elections to the two houses of parliament, the Chamber of Deputies and the Senate, could also drag on for months.
As things stand, the lower house would be elected by a system under which the largest party is guaranteed a majority of seats while the Senate would be voted in under a proportional representation system.
Most observers agree that this is a recipe for chaos but the situation could be simplified at the end of January, when the constitutional court is due to rule on the legitimacy of the new winner-take-all system for the Chamber of Deputies.
Before then, Gentiloni will have to handle a long-feared banking crunch centred on the ailing BMPS.
The bank's share price has fallen by 85 percent this year after another slide on Friday, when it emerged that the European Central Bank is refusing to grant any more time for it to raise badly-needed new capital from private investors.
Analysts see a state financed rescue as inevitable but, under EU rules, that can only happen if private investors also take a hit.
The issue is difficult politically with BMPS because of the large number of small investors who hold the bank's junior bonds.
Imposing losses at smaller banks last year caused outrage in Italy and damaged Renzi's standing.