|Sarkozy's pension reform has triggered a showdown with unions that sunk a previous effort 15 years ago
French transport workers are holding a second day of strikes as unions attempt to pressure the government to end plans that would see the age of retirement raised.
Train and bus services were disrupted on Wednesday, a day after between 1.2 and 3.5 million people marched in nationwide protests against the pension reform - the largest turnout in four demonstrations over the last five weeks.
French unions have voted to extend a rail strike and blockaded supplies from oil refineries and the country's largest fuel port, in what is becoming a showdown with Nicolas Sarkozy, the French president.
The action threatens to bring fuel shortages, with strikes shutting down 70 per cent of France's oil refining capacity.
"We are hardening our stance," Charles Foulard, head of the CGT union's branch at the French oil giant Total, said on Wednesday.
But Sarkozy has stood firm on his proposals, insisting that the government will stick to the reform, which will see the retirement age raised from 60 to 62.
The French senate backed the measure on Monday as part of a deeply unpopular pension reform bill.
'Risk of radicalisation'
Jacky Rowland, Al Jazeera's reporter in the southern French port city of Marseille, said workers were determined to make the government change its mind.
"French workers have campaigned long and hard for their rights and benefits, and they won't give them up without a fight," she said.
"They do remember that in the past - in 1995 and in 2006 - protest movements like this did force governments to back down on this kind of legislation.
"But it's by no means clear that it is going to happen this time around."
Three prior protests attracted crowds numbering in the hundreds of thousands but have not halted Sarkozy's pension reform plan.
"The government is taking the risk of a radicalisation of the movement," Francois Chereque, the head of the powerful CFDT union, said.
Sarkozy faces re-election in 2012 and his opinion poll ratings are at all-time lows.
Monday's vote, which came in at a narrow 174 to 159, shut the door on the most controversial aspect of the reform package, which Sarkozy's administration hopes to pass by the end of the month.
The senate also voted to raise the minimum age to receive a full state pension from 65 to 67.
Oil industry strike
Workers in the oil industry have also joined in the strike.
Employees at France's biggest oil port, Fos-Lavera, have now halted work for 15 straight days.
Like other European governments looking at austerity measures, France faces a deficit and a need to improve its finances if it hopes to retain a AAA credit rating, enabling the country to borrow money at a lower interest rate.
The reform bill has already been approved in its entirety by the lower house of France's parliament, the national assembly.
The senate is now voting on it piece by piece.