The French government has tried to calm fears of nationwide fuel shortages as strikes against pension reforms start to bite two days ahead of another wave of mass protests.
Officials were desperate to head off panic buying at petrol stations amid industrial action in which hundreds of thousands of people have taken to the streets in protest against the president Nicolas Sarkozy's key reforms.
Dominique Bussereau, the French transport minister, admitted that with 10 out of France's 12 oil refineries shut by industrial action, panic buying had led to a 50 per cent jump in petrol sales last week as hundreds of petrol stations risked running dry.
But Jean-Louis Schilansky, the head of the French Oil Industry Association, said service stations were now being replenished after the government authorised the use of extra-large 44-tonne trucks, usually banned for environmental reasons. "We have 'almost normal' means to deliver to petrol stations," Mr Schilansky said.
The French government has given oil companies permission to tap into their own emergency stocks but has resisted calls to use government-controlled strategic reserves ahead of tomorrow's day of mass protests, the sixth in as many weeks.
But unions slammed the reopening of a crucial pipeline to Paris-Roissy-Charles de Gaulle Airport, which officials warned could have run empty as early as today, saying untested fuel was flowing to planes.
"Turning the pumps on again was done secretly Ö by a handful of managers who are absolutely not trained for this kind of operation, at the ministry's behest," said Philippe Saunier of the powerful CGT union. "This creates a very big safety problem.
"Under these conditions, the strikers, who up to now were ensuring the safety of the site, have decided to let management face up to its responsibilities. Safety is no longer ensured at the oil depot."
This will be a make or break week for Mr Sarkozy's unpopular pension reform, which is set to increase the age of retirement from 60 to 62. Rail and refinery workers and lorry drivers are among those planning to increase the pressure to scrap it before a crucial Senate vote.
Throughout months of opposition to his plan to raise the retirement age as part of a blueprint to reduce a ballooning pension deficit, Mr Sarkozy has vowed not to cave in to the country's powerful unions.
For their part, the unions, who have a history of crushing reform, have vowed to match his resolve.
With petrol pumps drying up, lorry drivers threatening to block key roads and the public planning more nationwide marches, this week will put the president's ambition to the test.
Shortages could hit transport much harder if delivery drivers manage to halt road transport today and if protesters hit the streets in force tomorrow, the day before the French Senate is due to vote on Mr Sarkozy's bill.
"I think we're clearly at a crossroads. What I hope is that reason will prevail and that this reform can be adopted in the coming days and implemented in the coming weeks," said Bruno Le Maire, the minister for agriculture.
Unions are betting the next in a series of protests since the summer will have more clout if combined with fuel shortages, cancelled trains and transport disruption on roads.
Lorry drivers, the big guns of French protests because of their ability to block major motorways and disrupt the transport of vital goods such as food, started to block roads yesterday.
French union leaders say they will not give up until the government drops the bill and invites them to the table to have their say in any pension overhaul.
Charles Foulard, the CGT union co-ordinator for Total, said striking refinery workers had no intention of conceding.
"There is a toughening of resolve," he said. "The truck drivers are going to join us Ö We will go until the end."
* with Agence France-Presse and Reuters