ROME — After 14 months of bickering, Italy’s government collapsed on Tuesday, plunging a key European nation already hobbled by financial fragility and political chaos into a renewed period of crisis and uncertainty.
During the government’s short tenure, the nationalist-populist coalition struck fear into the heart of the European establishment. It antagonized the European Union, flouted its budgetary laws, demonized migrants and embraced President Vladimir V. Putin’s Russia and his strongman politics.
But any relief could be short-lived among critics who have accused the government of isolating and weakening Italy as it drastically reoriented the country’s place in Europe.
The government coalition of the hard-right, anti-migrant League party and the anti-establishment Five Star Movement came apart after a mutinous power play by Matteo Salvini, the League leader and the country’s increasingly popular interior minister.
This month, Mr. Salvini, 46, announced that he was fed up with the Five Star’s incompetence and inaction and made a bid for early elections, asking Italian voters to give him unrestrained power to consolidate his grip on the country.
Mr. Salvini may yet get his wish. But for now there remains the chance that his lengthening list of political enemies could form a new coalition government that freezes him out of power. At least immediately, things haven’t gone as Mr. Salvini had planned.
In an extraordinary session of Parliament Tuesday that interrupted the usually sacrosanct Italian summer recess, Prime Minister Giuseppe Conte accused Mr. Salvini, seated beside him with chin raised, of ‘‘political opportunism’’ for pulling his support from the government in hopes of taking power for himself.
The betrayal had thrust the country into a “vortex of political uncertainty and financial instability,” Mr. Conte said. Rather than bothering with a confidence vote that Mr. Salvini had pushed on him, the prime minister said he would tender his resignation to Italy’s president, Sergio Mattarella, collapsing the government and leaving Mr. Salvini with no immediate path to power.
Mr. Mattarella will now begin the process of consulting with party leaders to see if a new majority can form yet another Italian government. If not, he is likely to call for early elections, potentially as soon as October.
Mr. Salvini responded that he did not fear the judgment of Italians, unlike others in Parliament who were, he said, clinging to their jobs out of fear of losing elections. “We aren’t scared,” he said.
“If good God and the Italian people will let me come back to the government,” Mr. Salvini said in the Senate, as he spoke proudly of his closing of Italy’s ports to migrants, “I’ll do it again.”
Since the March 2018 election that brought them to power, Mr. Salvini and his Five Star counterpart, Luigi Di Maio, had turned the country into a social media reality show, incessantly speechifying and bickering via Facebook Live or Twitter over their opposite positions on infrastructure projects, taxes, regional autonomy and even beach holidays.
On Tuesday, Mr. Di Maio, 33, could hardly suppress his glee as Mr. Conte, standing between him and Mr. Salvini, accused the interior minister of exploiting Catholic symbols on the campaign trail and of failing to answer accusations that his League party had secretly sought funding from Russia.
“Dear Matteo, pushing this crisis you have assumed a great responsibility,” Mr. Conte said, adding that he “was worried” by Mr. Salvini’s request for full powers and for his supporters to fill the country’s squares in protest.
Over the past year, Mr. Salvini’s popularity has doubled to nearly 40 percent, considered a ceiling in Italy’s fragmented politics, as he has consistently outflanked and embarrassed the inexperienced Five Star Movement.
Five Star’s support halved, making elections perilous for its members’ continued employment in Parliament.
As Mr. Salvini’s support increased, he has eschewed Italy’s traditional alliances for closer relations with nationalists in Hungary, Poland and Russia. In the meantime, the country’s financial situation has darkened.
Growth has hovered around zero percent, and the government proved ineffectual in the face of dizzying youth unemployment and a public debt of more than 2 trillion euros — about $2.2 trillion — that represents more than 130 percent of Italy’s annual economic output.
The yield spread between Italian and German 10-year benchmark bonds, considered a metric of risk for investment in Italy, has stayed high through much of their tenure.
This month, Mr. Salvini used the government’s paralysis on infrastructure projects as a rationale to announce the death of the government — “the majority is no more,” he said — and call for new elections. “Let’s hear from the voters, quickly,” he said.
That is something the Five Star Movement, and many of Mr. Salvini’s other rivals, are not eager for at a moment when the interior minister’s popularity is riding so high. The prospect of elections has increased their incentive to strike a deal of their own to govern.
Feeling betrayed by Mr. Salvini, the Five Star Movement has seemed increasingly open to an alliance with its longtime rivals in the center-left Democratic Party.
For years, Mr. Di Maio and former Prime Minister Matteo Renzi, still a power broker inside the Democratic Party, have been sworn enemies. Now, however, they may find common cause in avoiding new elections, staying in Parliament and depriving Mr. Salvini of his power and campaign-friendly perch as interior minister.
But whether the two can overcome their mutual animosity to form a majority is still unclear and is the subject of behind-the-scenes negotiations.
Mr. Renzi, speaking in the Senate, argued that while populism works well on the campaign trail, “it works less good when we are dealing with governing.” He also took a parting shot at Mr. Salvini, who he said owed it to Italians to make it clear if he wanted to “leave the euro, or enter the ruble.”
Mr. Renzi spent the past few years vowing never to join forces with Five Star, accusing it of spreading hate, misinformation and a dangerous anti-expertise ethos.
But in recent days he has changed his tune as an alliance with Five Star may now provide an oxygen tank for a remarkable political resuscitation.
Mr. Mattarella, the head of state who is imbued with enormous powers during a government crisis, also has his motivations for avoiding early elections, which the Italian Constitution says should be a last resort.
The most pressing reason is the need for a government that can avoid an automatic hike in sales taxes by approving budget cuts to balance out Italy’s expensive programs and extraordinary debt by the end of the year.
If no new political majority forms, Mr. Mattarella can appeal to Parliament’s institutional figures, including the speakers of both houses, to try to form a government that can survive a confidence vote.
Another option is for Mr. Mattarella to empower a technical government of nonpartisan experts, which, once validated by a confidence vote, would also have the ability to pass a budget and govern.
If those options proved impossible, Mr. Mattarella could install a time-limited government to shepherd Italy through early elections, most likely in October or November, but probably denying it the time to devise a budget plan.
Meanwhile, Italy, already struggling financially and seeing its influence decline abroad, finds itself in a mess of its own making. And the crisis is likely to fuel the forces that have made Mr. Salvini the most popular, if no longer powerful, politician in the country.
Mr. Salvini’s support “won’t disappear overnight,” said Giovanni Orsina, a political scientist at Luiss, a university in Rome.
The League leader’s political opponents, he said, were betting they could sap Mr. Salvini’s support and momentum by delaying elections long enough for Italians to grow tired of him.
That plan, he said, could backfire and increase Mr. Salvini’s public support. “If there’s one things voters don’t like,” he said, “it is to feel their opinion doesn’t matter.”