French MPs voted on Wednesday evening in favour of a no-confidence motion that toppled Barnier, leaving France without a government.
There were immediate calls for Macron himself to resign and trigger fresh presidential elections, and his office said that he would make a TV address to the nation on Thursday at 8pm.
The no-confidence motion was supported by 331 of the 577 MPs in parliament after Marine Le Pen's far-right Rassemblement National and the leftist coalition Nouveau Front Populaire voted together to bring down the government.
Barnier is now legally obliged to stand down and his government has fallen. The French press has reported that he will hand his resignation in at 10am on Thursday, though he is likely to stay on in a caretaker capacity until a new prime minister can be appointed.
What happens next now the French government has fallen?
"We are now calling on Macron to go," Mathilde Panot of the far-left La France Insoumise (LFI) told reporters after the vote. Panot urged "early presidential elections" to solve a deepening political crisis.
"Finally, Barnier's government has fallen, along with his violent budget. Bringing down Barnier is respecting the vote of the French and the sovereignty of people.
"The chaos is not us, it is Emmanuel Macron, and by this vote, it is all of Macron's politics that have fallen," she said.
Leader of LFI, Jean-Luc Mélenchon posted: "The inevitable vote of no-confidence has taken place. Even with a Barnier every three months, Macron won't last three years."
La censure inéluctable a eu lieu. Même avec un Barnier tous les trois mois, Macron ne tiendra pas trois ans.
— Jean-Luc Mélenchon (@jeanlucmelenchon.bsky.social) December 4, 2024 at 8:34 PM
Meanwhile, Marine Le Pen herself, in an interview with French news network TF1, said "Emmanuel Macron is the main culprit in the current situation. The choice we have made is to protect the French. It's not a happy one. There was no other solution than this."
As for Barnier's supporters, member of the right-wing Les Républicains party, Valérie Pécresse on X called it a "sad day for France.
"Michel Barnier tried to get the country back on track. He set the goal of putting our finances and borders in order. Today, the RN, in an unholy alliance with the LFI, which has already subjected the entire left to its demands, is playing the worst kind of politics for the country and our compatriots!"
Debates in the Assemblée nationale lasted for around three hours on Thursday evening.
As they ended, Barnier himself addressed the parliament, insisting that compromise could still be possible and warning that: "The economic reality is that France's deficit problems will not disappear with a no-confidence vote."
He added: "It was not for pleasure that I presented difficult financial measures" and warned that the collapse of the government would have severe consequences for the French, saying "they will see a rise in the cost of living, their taxes will rise."
READ ALSO What happens next if the French government falls?
Brought in by President Emmanuel Macron in September to run a minority government after inconclusive parliamentary elections, Barnier, 73, first become a French member of parliament aged just 27 in the 1970s and entered government in the mid-1990s under the then-president, the late Jacques Chirac.
He also worked in Europe and is best known for being the EU's Brexit negotiator following the UK's 2016 vote to depart from the Bloc.
When he replaced Gabriel Attal in September, Barnier became the oldest prime minister in modern French history, at more than twice the age of his predecessor.
Barnier has said that he had accepted the thankless task of becoming prime minister as "an honour", but had no desire to hold on to the job at all cost.
"I am proud to serve, very honoured to be prime minister," he said in a prime-time television interview on Tuesday from his elegant prime ministerial office.
"But the gold decorations all around us, the official limousines and all the trappings of power of the republic? I couldn't care less about those," he said.
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