The number of demonstrators increased slightly compared to a first round of protests on January 19, putting pressure on the government which is struggling to convince voters of the need for the changes.

“The government must hear the massive rejection of this project and withdraw it,” Patricia Drevon from the Force Ouvriere union told a joint press conference with other labor leaders on Tuesday evening.

Two more days of strikes and protests were announced for next week on Tuesday and Saturday.

Macron’s plan to raise the age of retirement from 62 to 64 is a flagship policy of his second term in office which he defended on Monday as “essential” given forecasts for deficits in the coming years.

“The reform of the pension system is causing questioning and doubts. We hear it,” Prime Minister Elisabeth Borne wrote on Twitter on Tuesday, while insisting on the government’s “responsibility” to carry out the changes.

Unions claimed turnout nation-wide on Tuesday was around 2.5 million, with the hard-left CGT suggesting 2.8 million earlier in the day.

Strikes crippled transport, schools and other public services around the country.

“It’s one of the biggest demonstrations organized in our country in decades,” the head of the moderate CFDT union, Laurent Berger, said as a large crowd dominated by union members, public sector workers and students began marching in Paris.

The last comparable protests were in 2010 — also against pension reform — which reached 1.23 million people at their peak according to official figures, and 3.5 million according to unions.

Despite the prospect of an increasingly bitter and costly stand-off, Macron has shown no sign of stepping back over an issue that has put his credibility on the line only nine months after his re-election.

France currently has the lowest qualifying age for a state pension among major European economies and spends the second-highest amount on pensions relative to the size of its economy compared to other industrialized countries, according to OECD data.

“We need people to join the movement, rolling strikes that have a real impact,” Viviane Rongione, a retired teacher, told AFP as she marched on Tuesday. “Protests every 10 days won’t be enough to make the government back down.”

Tuesday’s demonstrations were peaceful, but minor scuffles broke out in Paris in the afternoon between anarchist and far-left activists and police. Police said they had arrested 18 people.

Large crowds also took to the streets in the rest of the country including in Marseille, Montpellier, Lyon, Nantes and Bordeaux.

“I don’t want to wait until I’m 64. I’m a nursery schoolteacher and it’s impossible to teach until that late in life,” said Sandrine Carre, 52, in the southwestern city of Bordeaux.

“We’re always having to crouch down, and already my knees hurt.”

The most controversial part of the overhaul is hiking the minimum retirement age, but it would also increase the minimum number of years needed to qualify for a full pension.

Opponents say the measures penalize the unqualified or unskilled workers who tend to start their working lives much earlier than graduates.

In the southwestern city of Toulouse, flight simulator repairman Christian, 54, said he could not wait until he was 65 to receive the maximum allowance.

“I’m already doing night shifts and it’s getting tougher,” he said.

Across the country, millions had to adapt their daily routines as workers in transport and education staged walkouts.

The SNCF national railway company said it had canceled 65 percent of high-speed TGV trains and 75 percent of regional trains.

France’s oil industry was mostly paralyzed, with the CGT union at energy giant TotalEnergies reporting between 75 and 100 percent of workers on strike.

Public opinion is likely to be crucial in the coming weeks as the government looks to swiftly pass the legislation in parliament and unions prepare more public defiance.

Sixty-one percent of French people support the protest movement, a poll by the OpinionWay survey group showed on Monday — a rise of three percentage points from January 12.

“The more French people find out about the reform, the less they support it,” said Frederic Dabi, a prominent pollster at the Ifop institute. “This is not good at all for the government.”

Macron’s centrist allies, short of an absolute majority in parliament, will need votes from conservatives to push through the new legislation.