ROME: Italian Prime Minister Giuseppe Conte pleaded for lawmakers' support on Tuesday as his teetering government faced a confidence vote while it struggles to battle the coronavirus pandemic.

The ruling coalition has been on the brink of collapse since former premier Matteo Renzi withdrew his Italia Viva party last week, depriving Conte of his majority in the upper chamber.

Conte, who since 2018 has headed two politically divergent governments, is desperately seeking the backing of opposition lawmakers to allow his coalition to stay in power.

"We are calling on all political forces, and also parliamentarians, who have Italy's destiny at heart to help us restart as quickly as possible," he told the upper chamber.

The prime minister has repeatedly warned of the danger of leaving Italy rudderless in the middle of a pandemic that has claimed more than 82,000 lives and devastated the economy.

His government won a first confidence vote late Monday in the lower house, but faces a tougher task persuading the Senate, where it lost its majority following Italia Viva's defection.

In a twist, Renzi's party said it would abstain, making it easier for the government to win the vote on Tuesday evening -- but the crisis risks being merely delayed.

Conte was widely expected to take around 155 votes in the 321-seat chamber -- saving the day, but with only enough support to keep going as a minority government.

Minority governments are nothing new in Italy, which has had 29 prime ministers and 66 governments since 1946.

But the task facing this one is unprecedented, with parts of the country currently under partial lockdown and a 220-billion-euro ($267 billion) European Union recovery package to push through parliament.

"Conte would end up commanding an extremely shaky majority that would risk collapsing at any divisive vote in the coming months," said Wolfango Piccoli of the Teneo consultancy.

Conte's coalition is made up of the former anti-establishment Five Star Movement (M5S), the centre-left Democratic Party (PD) and a smaller leftist party.

If they win on Tuesday, they will hope over the coming weeks to persuade a few renegade Christian Democrat, conservative and socialist lawmakers, as well as former M5S members and defectors from Renzi's side, to join them.

The knife-edge nature of the vote was demonstrated by the decision of some lawmakers to attend despite coronavirus restrictions.

Liliana Segre, a 90-year-old Holocaust survivor and non-partisan lifetime senator, said she would contradict her doctor's advice to travel from Milan to Rome to cast her vote for Conte.

Italy was the first European country to face the full force of the pandemic early in 2020 and has been one of the EU's hardest-hit countries.

It has been allocated a large share of a 750-billion-euro ($904 billion) European Union rescue fund, but Conte's 220-billion spending plan was a trigger for the current turmoil.

For weeks, Renzi had criticised Conte for his leadership style and his handling of the pandemic, and warned that he and M5S risked squandering the EU billions.

Critics in turn accused Renzi -- whose Italia Viva party is polling at just three percent -- of seeking to deliberately destabilise the government so he can play kingmaker.

Conte compared Renzi on Tuesday to "someone who constantly fills the common path with mines" and said he found it "very difficult" trying to govern while being under attack.

If Conte loses Tuesday, he could resign and seek to form a new cabinet, or PD and M5S -- and even Renzi -- could go on without him.

Another option might be a technocratic government, probably led by a non-partisan figure, to see Italy out of the worst of the Covid-19 crisis.

The nuclear option is snap elections, which none of the ruling parties want.

Opinion polls point to victory for the centre-right coalition comprising Silvio Berlusconi's Forza Italia and Matteo Salvini's far-right League party.

In both speeches to the Chamber of Deputies and Senate, Conte appealed for support from lawmakers from "the highest European tradition -- liberal, popular and socialist".

He was heckled by opposition lawmakers shouting "Go home!", while Salvini tweeted: "The sooner this government goes, the better for the country."