Baku, December 5 AZERTAC

Italian Prime Minister Matteo Renzi is set to resign on Monday after suffering a crushing defeat on Sunday in a referendum on constitutional reform, tipping the euro zone's third-largest economy into political turmoil.

According to Reuters, the euro briefly tumbled overnight to 20-month lows against the dollar, as markets worried that instability could reignite an EU debt crisis and deal a hammer blow to Italy's fragile banking sector, especially the troubled Banca Monte dei Paschi di Siena. However, by early in the European morning it had largely rebounded.

About 33 million Italians, or more than two-thirds of eligible voters, cast ballots following months of bitter campaigning that pitted Renzi against all major opposition parties, including the anti-establishment 5-Star.

Mattarella will consult with party leaders before naming a new prime minister -- the fourth successive head of government to be appointed without an electoral mandate, a fact that underscores the fragility of Italy's political system.

The vote ended months of campaigning for a reform that Renzi had said would bring political stability to Italy -- but that opponents said jeopardized democratic checks and balances.

The new prime minister, who will need the backing of Renzi's Democratic Party (PD) to take office, will have to draw up a new electoral law, with 5-Star urging a swift deal to open the way for elections in early 2017, a year ahead of schedule.

"From tomorrow, we will start work on putting together 5-Star's future program and the team of people that will make up a future government," said Luigi Di Maio, tipped to be the group's prime ministerial candidate.