Italy's former premier Matteo Renzi said on Wednesday he was pulling his party's ministers from the cabinet, effectively leaving the ruling coalition without a majority in parliament.
His decision, announced at a news conference, throws Italy into political chaos even as the country is struggling to contain the resurgent Covid-19 pandemic.
Renzi, who heads the tiny Italia Viva party, had long threatened to quit the government, complaining about Prime Minister Giuseppe Conte's plans over how to spend billions of euros promised by the European Union to relaunch the economy.
After conferring with Italy's head of state, President Sergio Mattarella, Conte had expressed hope that Renzi’s support would remain.
“Otherwise, a [government] crisis wouldn't be understood by the country,” Conte told reporters.
Mattarella has said that if the current government collapses, he may pull the plug on the legislature and trigger early elections rather than risk an alternative coalition with fragile support in parliament.
Opinion polls have consistently shown that any quick return to the ballot box would reward centre-right forces, including the right-wing League of Matteo Salvini and the nationalist Brothers of Italy.
Conte's main partners in the current 16-month-old government are the populist 5-Star Movement and the centre-left Democratic party. This coalition had replaced another also headed by lawyer Conte that included Salvini's Eurosceptic party and the 5-Stars.
With Renzi's support gone, Conte could attempt a cabinet shuffle. Alternatively, Mattarella could seek out a non-political figure to lead a government.
Two names have been touted by political commentators: Mario Draghi, the former European Central Bank chief, and Marta Cartabia, who formerly headed Italy's constitutional court.
Renzi has brushed off criticism that he is irresponsibly provoking a government crisis in the middle of a pandemic.
“What we’re doing is called POLITICS: studying the cards and making proposals,” he tweeted.
The former PM is known for his power plays. He became Italian premier in 2014 after he manoeuvered the governing Democratic Party to oust Enrico Letta.
Renzi, though, lost a political gamble two years later when he staked his premiership on a constitutional referendum that failed, forcing him to resign.
He later broke with his fellow Democrats and formed the Italia Viva party, which, while small, has enough support in the Senate to make his voice count in the government.
On Wednesday, Health Minister Roberto Speranza decried the tensions threatening the viability of Conte's coalition. He said Italy's aim is "too important to sully it with useless polemics that hurt everyone, and in particular the Italians who, with the vaccine, can and must get out of this long nightmare that we are living”.