Matteo Renzi, leader of Italy's ruling centre-left Democratic Party on Wednesday positioned it as a "bulwark" against billionaire media mogul and ex-premier Silvio Berlusconi's Forza Italia party, the grassroots Five-Star Party, and the anti-migrant Northern League in polls next year.
"At the next elections, a grouping will be born that will represent the only alternative to Berlusconi, the Northern League or the Five-Star Movement," Renzi said in Rome.
Taking a swipe at critics, Renzi warned: "Whoever weakens the Democratic Party weakens the bulwark against the populism of Five-Star and the Berlusconi-Salvini alliance."
Italy is due to hold national elections by next May and recent opinion polls show the centre-left, centre-right and Five-Star splitting the vote three ways, although Five-Star tops some polls.
The Five-Star Movement, which refuses to form political alliances, has accused a proposed new voting law backed by the Democratic Party of subverting democracy by allowing parties to form broad electoral coalitions.
Five-Star reckons that the new rules could cost it up to 50 seats in the lower house of parliament and wreck its chances of being the largest group in parliament after the elections next year.
The government hopes the lower house of parliament will this week approve the bill, which is also supported by Forza Italia and the Northern League. Five small parties are also backing the proposed law.
The bill will then pass to the upper house Senate, where the government lacks a clearly defined majority.
