Former French presidential candidate Jean-Luc Mélenchon has called on French voters to make him Prime Minister in June.

The 70-year-old head of La France Insoumise (LFI – Unbowed France), claimed granting his party a majority in the Assemblée Nationale would result in a "third round" of voting. Many of the 7.7 million individuals who voted for Mélenchon have stated that they would not vote.

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LFI was in urgent talks with ecologists and communists to establish a united front to fight the ultimate victor.

Mélenchon asked the French "to elect me prime minister. I ask them to elect a majority of MPs from La France Insoumise. And I call on all those who want to join the Popular Union [of the left] to join us in this beautiful combat.”

He reminded French voters it was the PM, not the president, who signed off government decisions. “I would be prime minister not by the grace and favor of M Macron or Mme Le Pen, but because the French wanted it,” he said, adding it would make the president “secondary”. He ruled out any negotiation with the new president.

In an interview with BFMTV, he stated that “If it does not suit the president then they can go because I will not."

Mélenchon would require the backing of the entire French leftwing electorate, around 11.8 million of whom voted in the first round, if he is to gain a majority in parliament following the elections on June 12 and 19. Mélenchon has flatly refused to form a coalition with the Socialist Party.

The leftist figure came first in the Paris department with 30.24 percent in the first round of the election, signaling increasing support from major departments.

Manon Aubry, an LFI MEP, told The Observer after spending last week negotiating with leftwing parties that  “There are obstacles, but there’s a common desire to create a union around a programme."

Antoine Bristielle, a political analyst and director of the Opinion Observatory at the left-leaning Jean Jaurès Foundation, stated that Melechon had learned his lessons from 2017.

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“After 2017, he didn’t succeed in maintaining high-level support for the subsequent elections, and he wants to do it differently this time,” Bristielle said.

“He’s trying to consolidate his base support and has realized the way to do this is from a position of force.

Laurent Joffrin, former director of the newspaper Libération, said LFI allies would be forced to "submit" instead of being allies, and give in to Mélenchon’s policies, including leaving the EU.

“This is the eternal problem of the radical left: it has a chance at power but in no way does it want to pull together to achieve it,” Joffrin stated.