Protesters scuffled with police at the Gare de Lyon station in Paris on Monday and union leaders threatened to ramp up action at oil facilities as a nationwide strike against government pension reforms went into a 19th day.
Riot police tangled with around 30 protesters at the Gare de Lyon, one of the French capital's busiest stations, footage from TV station BFM showed.
Protesters let off flares and fireworks, releasing smoke that drifted down into the station concourse.
The walkouts, which have disrupted Christmas preparations, have also affected other main Paris stations such as the Gare du Nord, which handles Eurostar services to London and Brussels, and the Gare de l'Est.
"I understand (the strike) but I am not OK with it as I think all French people are being held hostage and it is difficult for us to understand what the goal is," said Damien Dremont, a commuter at the Gare de l'Est.
Two weeks of nationwide industrial action against President Emmanuel Macron's pension reform, which would scrap special pensions for many public sector staff and make people work to 64 to draw a full pension, have crippled France's transport network.
OIL SECTOR
The hardline CGT trade union, which has been at the forefront of the industrial action, has said there will be no truce over Christmas and it will ramp up protests and shutdowns, particularly in the oil sector.
CGT's members are holding votes at refineries, oil depots and terminals on Monday to decide whether to shut down production at their plants as part of the protest.
The oil sector workers aim to intensify the strike by shutting down refineries to force the government to withdraw the planned pension reforms.
At the CIM oil terminal in northern France, which handles about 40% of French crude imports, CGT members decided to stay on strike but held off shutting down operations which would have cut crude deliveries to refineries and jet fuel to airports.
A CGT union official told Reuters that members voted on Monday to stop production at the LyondellBasell petrochemical complex in the south of France. Union members are expected to vote on whether to halt production at Total's Grandpuits refinery later on Monday.
LyondellBasell could not be reached for comment.
Shutdown procedure started early on Monday at PetroIneos' Lavera oil refinery in southern France after CGT workers voted halt operations.
Although the protests have disrupted deliveries, only about 2% of France's 11,000 petrol stations have run dry, according to oil sector lobby UFIP.
In a bid to defuse the public anger, Macron over the weekend decided to forego a special presidential pension payout when he eventually steps down. 
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