By Gavin Jones
ROME (Reuters) - Italy's co-ruling 5-Star Movement found itself without a leader on Wednesday after a row between its founder, comedian Beppe Grillo, and former Prime Minister Giuseppe Conte who had agreed to take charge of the struggling party.
5-Star is the largest group in parliament thanks to a triumph in 2018 elections, and its travails could have repercussions for the stability of Mario Draghi's national unity government.
Many 5-Star politicians and supporters have been unhappy with some of Draghi's policies and if the party splits up, as now seems likely, a significant number of its lawmakers could move into opposition.
On Wednesday Alessandro Di Battista, who recently quit 5-Star but remains highly popular among its voters, said it should hold an online vote of its members on whether to quit the coalition "after these tragic four months" of Draghi's government.
Draghi does not require 5-Star's votes for a parliamentary majority, but without them he would be fully dependent on those of the right-wing League, with its tough anti-immigrant and sometimes anti-EU positions.
Conte, who previously had no party affiliation, accepted Grillo's request that he take the reins of 5-Star, originally an anti-establishment protest party, after Conte's coalition government collapsed in January.
After spending months resolving internal disputes, Conte was finally ready to present his plans for a remodelled party along mainstream, centre-left lines, only for Grillo to block everything this week, angrily protesting he was being sidelined.
"Conte ... has neither political vision nor managerial skills. He has no experience of organisations and no capacity for innovation," Grillo, who founded 5-Star in 2009, wrote in a blog on Tuesday.
The 72-year-old former comedian said Conte had drawn up an archaic "17th century statute" for the movement he had founded on egalitarian principles based on direct democracy using the internet.
However, Grillo's post met with scores of negative comments from 5-Star supporters who accused him of trying to sink the movement he had founded.
Conte, who polls show is Italy's second most popular politician after Draghi, said on Wednesday that Grillo's "autocratic stance" was a "mortification for the whole 5-Star community".
With a reconciliation between the two men looking impossible, senior 5-Star politicians began to take sides, mostly against Grillo.
Vito Crimi, a party veteran and former caretaker leader, was among several senior figures who said they were considering quitting the party.
(Additional reporting by Angelo Amante; Editing by Giles Elgood)