By Angelo Amante
ROME (Reuters) - Italy's ruling anti-establishment 5-Star Movement has expelled a senator from its ranks on disciplinary grounds, in a fresh blow to the government's already small majority in the upper house of parliament.
The expulsion of Gianluigi Paragone comes less than a month after three 5-Star senators quit the party to join the far-right League opposition group, and will leave the fractious coalition with just a 5-seat majority in the 321-seat Senate.
"I was expelled from a nothing party," Paragone wrote on Facebook, referring to the 5-Star's sharp loss of popularity since obtaining 33% of the vote in the 2018 election. Latest polls put it at around 18%.
Paragone, a former TV presenter, voted against the budget bill and was a fierce critic of the pact the 5-Star signed in September with its old enemy the centre-left Democratic Party (PD) after its previous coalition with the League collapsed.
The expulsion further highlights the 5-Star's many problems, with party chief Luigi Di Maio facing criticism over his leadership and allegations from some dissidents of having betrayed the party's mission to overhaul the institutions.
Underscoring the divisions, party heavyweight Alessandro Di Battista leapt to the defence of Paragone, hailing him as a man who had defended 5-Star ideals. "There has never been a time when I have not been in agreement with him," he said.
Italy's upper and lower houses have identical powers and a coalition needs a majority in both chambers to govern.
Despite the slender official majority in the Senate, Prime Minister Giuseppe Conte can still rely on the backing of a small number of minority parties and unaligned senators who are not in the coalition but do not want an early election.
However, discontent within government ranks is growing over an array of issues, from justice reform to migrant rights, which could potentially tear the coalition apart.
In a bid to shore up the alliance, Conte has called for a meeting of the four coalition parties for Jan. 7 to try to thrash out a deal on some of the most contentious problems and put an end to the constant infighting.
Di Maio himself said on Wednesday that the ruling parties needed to draw up a new pact to establish policy priorities and to set out a timetable for their implementation.
(Editing by Crispian Balmer and Alison Williams)