Police fired tear gas at protesters on the Place de la Concorde in Paris, where some 7,000 people demonstrated against the government's pension changes in a spontaneous and unplanned rally.
he demonstration was across the river Seine from parliament, where Prime Minister Elisabeth Borne earlier on Thursday announced her government would push through the reform using a special constitution clause, as her minority government could not get the necessary backing from the opposition conservative Les Republicains party.
French unions plan another day of strikes and demonstrations against President Emmanuel Macron's pension reform, a union spokeswoman said on Thursday.
"The united union front continues to demand the withdrawal of the reform and calls for another day of strikes and demonstrations on Thursday, March 23," CGT union official Catherine Perret told a news conference.
President Emmanuel Macron's government on Thursday invoked special constitutional powers to push through a much-contested pension reform without a vote in parliament, where his centrist party does not have an absolute majority.
French Prime Minister Elisabeth Borne used a special procedure to push an unpopular pensions bill through the National Assembly without a vote on Thursday, triggering boos and shouts of "Resign!" in rare chaotic scenes in the French parliament.
The move will ensure the bill raising the retirement age by two years to 64 - which the government says is essential to ensure the pension system does not go bust - is adopted after weeks of protests and fractious debate.
But it also shows President Emmanuel Macron and his government failed to garner a majority in parliament, in a blow to the centrist president and his ability to win support from other parties for further reforms.
Borne was greeted by boos and jeers as she arrived in the National Assembly, the lower house of parliament, to announce that she would invoke article 49.3 of the constitution to skip a vote on the reform measures.
The session was suspended for two minutes after left-wing lawmakers singing the national anthem prevented Borne from speaking. Some held placards reading "No to 64 years".
When the session resumed, Borne took the floor but her speech was largely drowned out by the same boos and chants.
"We cannot gamble on the future of our pensions, this reform is necessary," Borne told lawmakers, to explain why she was using the 49.3 procedure.
Far-right leader Marine Le Pen said Borne should resign. "This last-minute resort to 49.3 is an extraordinary sign of weakness," she said, adding: "She must go."
Asked about a possible resignation in an interview with the TF1 television evening news, Borne said she still had a lot of work ahead of her: "There is the energy crisis, the climate crisis and the Ukraine war is continuing," she said.