Italy’s history of political instability resurfaced in particularly unstable times on Wednesday as a government crisis began in the midst of a pandemic that has devastated the country, raised doubts about the competence of its leadership and intensified political turf battles.

The government, a wobbly coalition of convenience between increasingly unpopular populists and the center-left establishment, seemed to verge on implosion amid long-simmering power struggles, revenge plots and ideological disputes over E.U. bailout funds.

Italy now finds itself in a familiar period of political uncertainty, but one that is much more dangerous given the pandemic.

The crisis was triggered by the withdrawal of government ministers by a former prime minister, Matteo Renzi, who controls a small but critical support in the governing majority. His gambit, which nervous political leaders spent the week trying to avoid, forces his rival, Prime Minister Giuseppe Conte, into a difficult position.

The opening of a government crisis comes as Italy, the first European country to be strongly hit by the virus and among the most devastated by it, is embarking on a vaccination program upon which the nation’s hopes rest.

Italian voters, who largely do not understand or care about the machinations and battles among political leaders, are concerned that the breakdown might hamper Italy’s virus response and delay the return to a semblance of normalcy.

At a Wednesday evening news conference, Mr. Renzi, a center left politician, officially announced the resignation of two of his ministers. He did not rule out joining another government led by Mr. Conte, but said that the prime minister had forced his hand by using the pandemic as a pretext to circumvent democratic institutions.

“Exactly because there is the pandemic, there is the need to respect the rules of democracy,” he said.

Expressing a tacit complaint among many in the Democratic Party, which he once led, Mr. Renzi said that the government’s more populist members focused more on receiving likes on social media than seriously governing. He said Mr. Conte’s government had failed to move forward on infrastructure projects, to invest in jobs for Italy’s youth, and to sufficiently condemn the supporters of President Trump who stormed the U.S. Capitol building a week ago.

Most important, he said, ideological populists in Mr. Conte’s government had refused to accept billions of euros in bailout money from the European Union for Italy’s health system.

The reaction to Mr. Renzi’s break was swift and negative from across the Italian political landscape, with leaders lamenting that Mr. Renzi’s move was unreasonable, politically motivated, and had thrust the country into the abyss.

“A grave error made by a few that we will all pay for,” Andrea Orlando, a former ally of Mr. Renzi in the Democratic Party wrote on Twitter.

Mr. Conte’s administration could manage to keep a parliamentary majority, potentially through a reshuffle of the current cabinet. But that gets more difficult without Mr. Renzi’s approval.

Mr. Conte may also just resign, prompting the collapse of the government in the middle of the worst national crisis Italy has faced since World War II. Italy’s president could then ask someone with enough support, maybe even Mr. Conte again, to build another government that would receive approval in parliament.

But if a new and durable coalition cannot be found, the political crisis could eventually prompt new elections in potentially dangerous conditions, and crack the door open to the return of nationalist forces.

Mr. Renzi’s critics, who are rife, see a vengeful and ambitious politician who now only had the power to destroy, but could not resist using it.

Mr. Renzi, a skilled political operator from the center-left establishment, effectively sidelined the nationalist leader Matteo Salvini in 2019. After Mr. Salvini overreached himself out of a governing coalition in a power grab, Mr. Renzi seized the moment, swallowing his considerable pride to create an unlikely alliance between the Democratic Party he once led and the populist Five Star Movement that had spent years spreading insults and disinformation about him and which had knocked him out of power. That deal prevented new elections that Mr. Salvini had been projected to win and kept him at bay.

Mr. Renzi then promptly left the Democratic Party and formed a small party, Italia Viva, that has failed to gain any real traction. But it has enough members of Parliament to be decisive for the survival of the government consisting of Five Star and the Democratic Party.

Tensions between Mr. Conte and Mr. Renzi broke into the open in December when Mr. Conte announced the forming of yet another task force to decide how to spend the more than 200 billion euros — about $243 billion — of the European Union’s Recovery Fund.

Mr. Renzi is also demanding that the government accept a separate sum of 36 billion euros — about $44 billion — made available by the European Union and earmarked for Italy’s health system. Five Star, which came to power expressing anti-establishment anger against Brussels, rejected the source of this funding, called the European Stability Mechanism, as anathema to its populist roots.

Journalists working outside Palazzo Chigi, the seat of the Italian government, on Tuesday. Credit...Vincenzo Pinto/Agence France-Presse — Getty Images

For weeks, Mr. Conte and Mr. Renzi have played a game of chicken. Mr. Renzi’s already basement-scraping popular support reduced the downside of doing something unpopular. Having nothing to lose gave him more leverage in his face-off with Mr. Conte, who had in fact caved on many of Mr. Renzi’s demands.

But the prime minister held firm on his refusal to take the European Stability Mechanism money.

In the run up to Mr. Renzi’s leap, Mr. Salvini, the populist leader, salivated at the prospect of another chance at power.

The populist leader Matteo Salvini is advocating for an election of a center-right government.Credit...Igor Petyx/EPA, via Shutterstock

“Better an election or a center-right government rather than this squabbling,” he told reporters on the margins of a protest in Rome.

On Wednesday night, Mr. Renzi said he opposed the possibility of new elections. To avoid that from happening, he could throw his support back to Mr. Conte, but in a crisis things are unpredictable and can get out of hand. For this reason, members of the government sought to pull Mr. Renzi back from the brink.

The most hard-line members of Five Star have ruled out ever working with Mr. Renzi’s party again if he causes the government’s collapse.

It’s unclear where that leaves Mr. Renzi, or Italy.

Some of Italy’s leading virologists are clearly disgusted by the political distractions in a health emergency.

“The orchestra is playing while the Titanic is sinking,” Massimo Galli, the director of the infectious disease department at the Luigi Sacco hospital in Milan, said on Italian television. “There is a chance that next week we’ll have hospitals in serious difficulty again.”