After some 800,000 protesters rallied in support of one of France's largest nationwide strikes in decades, unions announced plans for further industrial action against President Emmanuel Macron's overhaul of the pension system.

Catherine Perret, a senior member of France's biggest public-sector union Confédération Générale du Travail (CGT), told the media after a meeting of four unions: "Everybody in the street on Tuesday, December 10, for a new day... of strikes, actions and protests."

Transport chaos continues across the nation after Thursday's demonstrations and widespread strike action, with hundreds of thousands of workers entering their second day of mass walkouts. 

Rail operator SNCF reported that 90 percent of high-speed TGV trains had again been cancelled, with Air France, EasyJet and Ryanair just some of the companies to scrap flights.

Over half of Paris' 16 metro lines were closed with severe disruption to the seven routes that are still running, leading to 350 kilometres (220 miles) of traffic jams around Paris, some 120km above the region's average, according to traffic website Sytadin. Many French commuters took to bicycles and electric scooters instead to avoid the disruptions.

Fewer teachers were reportedly taking part in Friday's industrial action after around 55 percent of the country's teaching staff joined the mass walk out on Thursday.

The majority of the protests passed without violence. However, sporadic clashes broke out between police and demonstrators in several cities. Police were seen firing tear gas at protesters in Paris, while some members of the public attempted to smash shop windows and throw projectiles.

An investigation has been launched into a video showing two police officers beating a protester with batons while he is on the ground. The footage was captured on Boulevard de Magenta near Place de la Republique in Paris during yesterday's protest in Paris.

Health Minister Agnes Buzyn stated on Friday that the government was taking notice of the angry response to potential pension cuts, with meetings between officials and union leaders set for Monday. The government is yet to fully disclose its plans for pension reform, with Buzyn telling Europe 1 radio that "there is indeed a discussion going on about who will be affected, what age it kicks in, which generations will be concerned ... all that is still on the table.”

At the time of writing Macron had not yet spoken publicly about the industrial action, but an unnamed presidential official said that the president was "calm" and "determined to carry out this reform."

The French president has called for a "universal" retirement system, which for workers in 42 "special regimes" - including rail, energy, and France's legal system - would see an end to early retirement and cuts to pensions.

Unions have also said that under the proposed legislation, millions of private-sector workers would have to stay in employment beyond the current legal retirement age of 62 to get the pension they had expected. Prime Minister Edouard Philippe, who is set to make the details of the pension reforms public on 12 December, has said that French workers will have to work longer under the new legislation.