A coalition on the left that came together unexpectedly ahead of France's
won the most parliamentary seats in the vote, according to polling projections.
The
just after the polls closed on Sunday evening local time put French President Emmanuel Macron's centrist alliance in second place and the far-right National Rally in third.
Soon afterwards, French Prime Minister Gabriel Attal said he plans to resign.
"Tonight, the (political) extremes have no absolute majority, thanks to our determination and the strength of our values. We (centrists) have three times more MPs than were predicted at the start of this campaign," Attal said.
"Being prime minister was the honour of my life. This evening the political group that I represent no longer has a majority and tomorrow morning I will submit my resignation to the president."
Attal said he will remain in post during the upcoming Paris Olympics and for as long as needed, given that polling projections show no party has won an outright majority.
The lack of a majority for any single alliance could plunged France into political and economic turmoil.
Macron's office said the president would "wait for the new National Assembly to organise itself" before making any decisions. The deeply unpopular president lost control of parliament, according to the projections.
Marine Le Pen's far right drastically increased the number of seats it holds in parliament but still fell far short of expectations.
The president of France's far-right National Rally claimed historic gains for the party and blamed Macron for "pushing France into uncertainty and instability".
Marine Le Pen's far-right National Rally party failed to achieve an expected majority of the votes. Source: ABACA / Lafargue Raphael/PA
In a sombre speech after the second-round legislative election, Jordan Bardella denounced the political manoeuvring that led the National Rally to fall far short of expectations.
An unprecedented number of candidates who qualified for the runoff stepped aside to allow an opponent to go head-to-head with the National Rally candidate, increasing the chances of defeating them.
Despite projections widely considered disappointing for the anti-immigration nationalist party, it still increased its seat count in parliament to an unprecedented high, according to polling projections.
"Tonight, by deliberately taking the responsibility to paralyse our institutions, Emmanuel Macron ... is consequently depriving the French people of any responses to their daily problems for months to come," Bardella said.
French leftist leader Jean-Luc Mélenchon called the projections an "immense relief for a majority of people in our country".
French leftist leader Jean Luc Mélenchon called the projections as "immense relief". Source: AAP / Andre Pain/EPA
Melenchon is the most prominent of the leftist leaders who unexpectedly came together during the two-round elections.
What happens now
The election will leave parliament divided into three big groups — the left, centrists, and the far right, with hugely different platforms and no tradition of working together.
There will likely be weeks of intense political negotiations to choose a new prime minister and form a government and Macron faces the prospect of leading the country alongside a prime minister opposed to most of his domestic policies.
With the Paris Olympics opening in less than three weeks, the country will be grappling with domestic instability.
