PARIS - French labour unions threatened to bring the nation to “a halt” in March as the number of protesters against government pension reform swelled to about a million on Saturday.

In the fourth day of action against the pension overhaul, which includes increasing the minimum retirement age to 64 from 62, some 963,000 people joined street demonstrations around France, according to government figures.

The number is higher than the previous round of action last Tuesday, when 757,000 people took to the streets. But it is lower than the 1.2 million record turnout registered on Feb 1.  

As with many marches in France, there were occasional clashes between some protesters and police.

The unions have concentrated their efforts on organising marches as well as calling for general strikes. They held the protest on Saturday, since many workers could not afford to forgo wages in repeated weekday walkouts. 

While protest drew the largest turnout in Paris so far, with 93,000 people, there was little disruption to services, with most trains and public transportation functioning normally across the country.

The exception was at Orly airport near Paris, where half the flights were cancelled in the afternoon.  

France’s most influential unions have called for another day of action on Feb 16, when the age measures of the reform are due to be debated at the National Assembly. 

In a joint statement, the unions threatened more radical actions, and said they’ll shut the country down on March 7 if the government doesn’t give in. The unions have millions of members across all sectors of the French economy, from teachers to bank workers, athletes and lawyers.

“We can do it,” Mr Laurent Berger, head of the CFDT union, told reporters on Saturday, citing full consensus between labour organisations on the need to step up pressure against Mr Macron. 

The breadth and dynamics of street protests in France have often proved make-or-break for past presidents’ reform efforts. In 1995, Mr Jacques Chirac’s government dropped a pension overhaul plan after crippling strikes. Prolonged student-led protests forced a U-turn on labour laws in 2006, even after Parliament had approved changes. 

President Nicolas Sarkozy in 2010 pushed ahead with raising France’s retirement age to 62 from 60 despite months of upheaval. Mr Macron now wants to lift it further, to 64.

Mr Macron has so far shown little sign that he would back down. Speaking on the sidelines of a summit of European leaders on Friday, the French President told reporters that unions must not “block the life of the rest of the country.” BLOOMBERG