Italy's opposition 5-Star breaks with co-founder Grillo

Italy's 5-Star Movement rally in Rome

ROME (Reuters) - Italy's 5-Star Movement severed ties on Sunday with its co-founder, the comedian Beppe Grillo, a further step in turning what was once a radical protest movement into a more mainstream left-leaning force.

In a series of reforms, 5-Star supporters also voted down a proposal to ban alliances with other parties, a move that could smooth relations with the main opposition Democratic Party (PD) and ultimately provide more of an electoral challenge to Prime Minister Giorgia Meloni's right-wing coalition.

Grillo, who helped to create the party in 2009, had retained a formal role as guarantor of its founding values, and an annual contract worth 300,000 euros ($313,000) as communications adviser.

However, party members voted 63%-29% in favour of abolishing the guarantor role in a decision announced at the end of a two-day "constituent assembly" event focused on reforming its statutes.

"I didn't expect our guarantor to get in the way, and go in with his studs up," said party leader Giuseppe Conte, using a soccer metaphor and illustrating the bad blood between the two men.

Conte has repeatedly clashed with Grillo since he took the reins of Italy's second-largest opposition party in 2021.

Grillo did not attend the party gathering. He had earlier posted a cryptic message on WhatsApp that read "From Franciscans to Jesuits", interpreted as a reference to a shift by the party from simple direct messaging to something more complex.

Grillo, known for his outspoken language, has in the past accused Conte of lacking political vision and criticised what he saw as an attempt to turn the once-maverick 5-Star into a traditional leader-centred party.

Grillo founded the movement with internet expert Gianroberto Casaleggio. Within a decade it won 32% of the vote at 2018 elections, double that of its nearest rival, and became the senior partner in a coalition government.

It has lost steam in recent years, weakened by internal bickering, and it currently has around 11% support ratings in polls.

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(Writing by Keith Weir; Editing by Ros Russell)