Motorists around France have been queueing to fill their fuel tanks, as strikes at oil refineries persist. Coupled with some panic buying, the disruption has led to fuel shortages in large parts of France.

France's CGT union is seeking to choke off power and fuel supplies and hamper the public transport network, in a showdown with a government that flatly refuses to withdraw a contested labour law reform. CGT warned the government that the European football tournament that opens in France on 10 June could be disrupted if it continues to refuse to back down.

France fuel petrol strike shortage
Drivers queue at a petrol station in Rennes, western FranceDamien Meyer/AFP

Tens of thousands of demonstrators took to the streets of cities around France and workers responded to the union call by stopping work at oil refineries, nuclear power plants and the railways, as well as erecting road blocks and burning wooden pallets and tyres at key ports like Le Havre.

France fuel petrol strike shortage
Youths break a bank window during a demonstration to protest the the government's proposed labour law reforms in NantesStephane Mahe/Reuters
France fuel petrol strike shortage
A French student wears a Sarkozy mask and holds a poster depicting French Prime Minister Manuel Valls during a demonstration against the French labour law proposal in MarseilleJean-Paul Pelissier/Reuters
France fuel petrol strike shortage
A riot police officer holds a shield covered in paint during a protest called by seven labour unions and students against labour and employment law reform, in BordeauxGeorges Gobet/AFP
France fuel petrol strike shortage
Security forces clash with demonstrators in Bordeaux, southwest FranceGeorges Gobet/AFP
France fuel petrol strike shortage
Workers block the access to the nuclear power plant of Nogent-sur-SeineFrancois Nascimbeni/AFP
France fuel petrol strike shortage
Tanker drivers and workers block a fuel depot in Ajaccio on the French Mediterranean island of CorsicaPascal Pochard Casabianca/AFP
France fuel petrol strike shortage
Workers on strike set up a burning barricade to block access to the harbour of Saint-Nazaire, western FranceJean-Sebastien Evrard/AFP

Prime Minister Manuel Valls insisted the government would not withdraw the law and said it would break up refinery blockades, saying there could be some tweaks to the reforms but not on any of its key planks. He was backed by the country's other big trade union, the CFDT.

After police intervention in recent days to lift blockades at refineries and fuel distribution depots, Valls said 20-30% of petrol stations were dry or short of certain fuels. Oil giant Total said all but one of its fuel distribution depots were working. It warned, however, that two of its five refineries in France were at a standstill and two more set to halt in coming days.

France fuel petrol strike shortage
A woman walks behind a placard which reads 'closed, dried up' at a petrol station in SavenayStephane Mahe/Reuters
France fuel petrol strike shortage
Petrol pumps display signs that read 'out of order' at a Total petrol station in Bouguenais near NantesStephane Mahe/Reuters
France fuel petrol strike shortage
Striking workers block the entrance of the fuel depot near the oil refinery of DongesStephane Mahe/Reuters
France fuel petrol strike shortage
French gendarmes remove branches, wood pallettes and tyres after striking workers blocked roads near the oil refinery at Fos-sur-Mer, near MarseilleJean-Paul Pelissier/Reuters
France fuel petrol strike shortage
French workers stand near a barricade blocking access to a fuel depot in DongesStephane Mahe/Reuters
France fuel petrol strike shortage
French workers and protesters walk near a barricade blocking the entrance to a fuel depot near the oil refinery in DongesStephane Mahe/Reuters
France fuel petrol strike shortage
A man wearing glasses emblazoned with the CGT union logo rallies outside the nuclear power plant in Nogent-sur-Seine, east of ParisFrancois Nascimbeni/AFP
France fuel petrol strike shortage
A striking worker passes graffiti reading 'Blockage' outside an oil depot near the Total refinery in Donges, western FranceJean-Sebastien Evrard/AFP

French nuclear power capacity was cut by as much as five gigawatts due to stoppages. That is equivalent to just over 6% of the country's total production capacity. With dockers striking at the southern port of Marseille, the number of ships waiting at sea to offload oil, gas and chemicals rose to 21 from what would normally be about five, the port authority said. hurting less than the previous week when a similar strike halved the number of trains running.

After months of rolling protests sparked by a reform that aims to make hiring and firing easier, the stoppages and street marches are being watched closely as a test of whether the CGT-led opposition is solid or at risk of fizzling out. The street marches were joined by scores of marchers from a youth protest movement called Nuit Debout (Night Rising). Police were deployed to counter risks of the fringe violence in which 350 police and several protesters have been hurt and more than 1,300 arrested at similar rallies in recent weeks.

The proposed law, aimed at boosting hiring after a decade of nearly 10% unemployment and slow but corrosive economic decline, has escalated into the toughest challenge yet to President Francois Hollande and his Socialist government. "There could be improvements and modifications" in the bill, Valls said on television. He didn't elaborate on what might be changed, and insisted that the "heart" of the bill — a measure weakening the power of unions over workplace rules — should remain. Withdrawing the bill "is not possible," he said.