The growing unrest, which has resulted in a wave of strikes since the start of the year and rubbish piling up on the streets of Paris, has left President Emmanuel Macron with the gravest challenge to his authority since the so-called Yellow Vest protests of December 2018.
Reuters TV broadcast images of tear gas used by police to deal with crowd disorder as protesters gathered in Paris' Place de la Concorde, near the Assemblee Nationale parliament building.
"Macron, Resign!" chanted some demonstrators, as they squared up to a line of riot police.
Friday's night trouble followed similar disorder on Thursday, after Macron decided to push through the contested pension overhaul without a parliamentary vote.
The overhaul raises France's state pension age by two years to 64, which the government says is essential to ensure the system does not go bust.
Unions, and most voters, disagree.
The French are deeply attached to keeping the official retirement age at 62, which is among the lowest in OECD countries.
More than eight out of 10 people are unhappy with the government's decision to skip a vote in parliament, and 65 per cent want strikes and protests to continue, a Toluna Harris Interactive poll for RTL radio showed.
A broad alliance of France's main unions said they would continue their mobilisation to try and force a U-turn on the changes. Protests are planned for this weekend, with a new day of nationwide industrial action scheduled for Thursday.
Teachers' unions called for strikes next week, which could disrupt the emblematic Baccalaureate high-school exams.
While eight days of nationwide protests since mid-January, and many more local industrial actions, had been largely peaceful, the unrest on Thursday and Friday was reminiscent of the Yellow Vest protests in late 2018 over high fuel prices, which forced Macron into a partial U-turn on a carbon tax.
Left-wing and centrist opposition lawmakers filed a motion of no-confidence in parliament on Friday afternoon.
But even though Macron lost his absolute majority in the lower house of parliament in elections last year, there was little chance this would go through - unless a surprise alliance of lawmakers from all sides is formed, from the far-left to the far-right.
Macron will want to turn the page quickly, with government officials already preparing more socially minded reforms. He can also choose, at some point, to fire Prime Minister Elisabeth Borne, who has been at the forefront of the pension debate.
But either or both moves may do little to quell anger on the streets. Neither of them had made public comments on Friday.Â
27°C