The leaders of Italy's opposition parties on Monday blamed their defeat on a lack of unity and on voters choosing a path of populism, after Giorgia Meloni's rightist bloc overwhelmingly won the national election.
Near final results showed the conservative alliance, which includes Meloni's Brothers of Italy, Matteo Salvini's League and Silvio Berlusconi's Forza Italia, on course for a solid majority in both houses of parliament.
Centre-left and centrist parties, who fought the election on their own after a series of bust ups, collectively won more votes than the right, but an electoral law that awards a third of seats on a first-past-the-post system favours broad alliances.
Enrico Letta, the head of the opposition Democratic Party (PD), announced he would stand down.
"My leadership will come to an end as soon as the (party) congress identifies a new one," he told a news conference at the PD headquarters in Rome.
Letta - whose party got around 19% of votes - said the rightist victory had its roots in the Five Star Movement (M5S)'s decision to withdraw support from the national unity administration of Mario Draghi last July.
This caused the resignation of the former European Central Bank chief, bringing to an end Letta's plans to forge a electoral alliance with the M5S, who got around 15% thanks to a strong performance in the south.
M5S leader Giuseppe Conte said overnight it was the PD's fault if it proved impossible for the centre left to win.
"They have undermined a political offer that could have been competitive against this centre right," Conte said.
Carlo Calenda, the leader of he centrist Action party who had initially signed on to an alliance with the PD but then backtracked, lamented that a large part of the country "has chosen a path of populism".
"This is a dangerous choice for the country, an uncertain choice, we will see if Meloni will be able to govern," he said, as his federation with the Italia Viva party garnered just under 8% of votes, against their stated aim of winning at least 10%.
(Reporting by Angelo Amante and Rodolfo Fabbri; Writing by Keith Weir; Editing by Agnieszka Flak, Alvise Armellini and Alison Williams)