Bitter and disappointed at Sunday night’s results in parliamentary elections, Jordan Bardella, the National Rally (RN) leader, warned that an unholy Left-wing alliance had thrown “France into the arms of Jean-Luc Mélenchon’s extreme Left”.

“The New Popular Front (NFP) is ready to govern,” intoned Mr Mélenchon, a former Trotskyist and self-styled leader of the hastily formed alliance that includes his France Unbowed (LFI) party, Communists, Greens and Socialists. In other words, the 72-year-old firebrand is ready and willing to step up to become France’s next prime minister. 

But the rest of the NFP, which came first in Sunday’s parliamentary runoff, would beg to differ. Francois Hollande, the Socialist former president who won a seat on Sunday, has described Mr Mélenchon as the “problem” rather than the “solution” to forming a government. The vast majority of French voters agree, polls have shown.

Mr Mélenchon, a divisive figure, has been nicknamed France’s Jeremy Corbyn. Suggestions of anti-Semitism have surrounded the LFI leader, who is critical of Israel, just as they did around Mr Corbyn. He strenuously denies the claims.

He has offered tepid support for Ukraine and previously appeared supportive not only of Vladimir Putin, but also of autocratic leaders in South America. Both Hugo Chavez, the late Venezuelan president, and China’s Chairman Mao have won his admiration.

Fanning the flames is his speciality. A year ago when youths rioted and pillaged for nearly a week across France in the wake of a police shooting of a teen outside Paris, Mr Mélenchon asked only that they spared schools, sports halls and libraries from being trashed.

When violence engulfed the French overseas territory of New Caledonia in May, costing the lives of several people, his response was: “The watchdogs order us to call for calm. We call for justice.”

During the campaign, President Macron warned that both the RN and Mr Mélenchon’s camp could lead France to “civil war” if elected.

He has already shown his brutal, sectarian side when during the lighting election campaign he “purged” LFI heavyweights deemed to have criticised their great leader. All five ran on an independent ticket and won in a major snub to the charismatic veteran.

Among those who he fell out with spectacularly is Francois Ruffin, MP in the Somme, who described Mr Mélenchon as a “boulet” ‘(liability).

On Monday, Marine Tondelier, the leader of the Greens, put it slightly more diplomatically, saying: “A good prime minister must calm the country down and rally support within his own party” - a nod at the internal ructions with LFI.

On Monday, party heavyweight Clémentine Autain said she was leaving LFI in disgust at his purge of fellow members and forming her own group. She ruled out Mr Mélenchon as PM.

Divisive figure

“He’s not the leader of the New Popular Front,” added Yannick Jadot, a Green politician, who said the alliance would pick a new prime ministerial candidate “this week”.

But the Mélenchon camp refuses to accept this analysis. “He is in no way disqualified,” said party loyalist Mathilde Panot. “Jean-Luc Mélenchon is the man who taught the Left how to win again, the man who restored hope to millions of people by winning 22 per cent of the presidential election (in 2022), the man who made it possible… for the New Popular Front to exist.”

He laid down the gauntlet an hour after the first results came in, saying the only option for Mr Macron was a full-scale Left-wing government led by his hardline party.

Analysts expect Mr Macron to attempt to forge a working coalition between his centrists and moderate Leftwingers. That would mean splitting away the Socialists, a former party of government under presidents Mitterrand and Hollande, and Greens from the hardliners of LFI.

Le Monde’s Nicolas Chapuis wrote: “Jean-Luc Mélenchon has tried to impose an uncompromising line, particularly on the New Popular Front programme. This scenario does not stand up to scrutiny for two seconds. The NFP does not have the means to govern alone.”

“If it wants to lead the country, it will have to find allies. Finding allies means making concessions, in particular programmatic concessions...The culture of consensus is not in the DNA of the Fifth Republic. Political parties need to learn this if they want to avoid deadlock.”

With figures like Mr Mélenchon in the mix, reaching consensus seems fanciful at best. But given his tub-thumping habits, don’t expect Mr Mélenchon to go quietly.