On a recent weekday, Saifi Ahlem caught a 5 a.m. Métro to get to her job as a passengers' assistant at Orly Airport, where she often works 44 hours a week — well over France's official 35-hour workweek.
That afternoon, she took a quick lunch break then headed to her second job, as a sales manager at the French hypermarket Carrefour, ending her day at 9 p.m.
"France has a reputation for having lazy workers," said Ms. Ahlem, 26. "But I've never worked just 35 hours. That would be like resting on my laurels."
More than a decade after it was introduced, the 35-hour workweek still projects an image of France as being one of the most laid-back places in the world to work. In most of the rest of the eurozone, the 40-hour workweek is standard.
But in reality, France's 35-hour week has become largely symbolic, as employees across the country pull longer hours and work more intensely, with productivity per hour about 13 percent higher than the eurozone average. And a welter of loopholes lets many French employers outmaneuver the law.
All told, French workers put in an average of 39.5 hours a week, just under the eurozone average of 40.9 hours a week, according to the Organization for Economic Cooperation and Development.
Now, a fight has broken out within President François Hollande's Socialist government over whether to officially end the nominal 35-hour workweek as a way to overcome France's economic malaise.
Breaking a taboo, Economy Minister Emmanuel Macron has begun to openly question whether the measure — which was passed in 2000 by a Socialist government to encourage job creation — still serves the country's needs.
Tensions rose sharply after Der Spiegel, the German news weekly, reported on Sunday that a German-French action plan, prepared for Mr. Macron and his German counterpart, Sigmar Gabriel, would call for overhauling the 35-hour week. After a storm of protest, French officials this week sought to calm fears that a major change was underway.
The report, which is to be made public on Thursday, "does not call into question" the current workweek, they said, although the government does see room for more flexibility within the framework of the law.
Last week, Mr. Macron, an economic centrist, told Parliament that the 35-hour rule had for too long painted France as "a country which no longer wanted to work," sending a negative signal to foreign companies wanting to invest here. Given France's economic challenges, Mr. Macron said, the 35 hours "should no longer be put on a pedestal."
His remarks provoked an immediate backlash within his Socialist Party and among trade union officials, who accused the government of threatening to tear down a totem of the French state that many still cherish.
Any effort to weaken the 35-hour standard "will not be implemented here in France," warned Bruno Le Roux, the president of the Socialist Party.
For wage earners like Ms. Ahlem, political resistance to change seems out of touch with economic reality. "We should really be encouraging people to work more if they want to — not the opposite," she said.
The law has not improved an unemployment rate that, at 10.2 percent, hovers near a high. Nor does it address a deeper challenge in the French workplace: the rising use of part-time contracts, which employers increasingly use to avoid the risk of paying costly overtime.
Ms. Ahlem has a pretax base salary of around 13.45 euros, or $17, an hour from Groupe 3S, which provides passenger services at the airport. She gets €10.78 an hour at Carrefour, which is better than France's €9.53 minimum hourly wage.
Ms. Ahlem would rather work full-time at Carrefour, where she is replacing a worker on leave. But so far she has been able to obtain only a part-time contract. Meanwhile, the 35-hour workweek rules — despite the loopholes — require her airport employer, Groupe 3S, to cap her maximum working time at 44 hours a week, limiting her earnings there.
"The 35 hours was an intellectual and economic mistake," said Dominique Moïsi, a senior adviser at the French Institute for International Affairs, an influential research group. "For Mr. Macron to say that he can touch that Holy Grail is very antagonistic to the French left. But it is a way of telling the outside world and the rest of Europe, we should reform France."
Mr. Macron insisted that he did not want to dismantle the law, which requires employers to provide paid rest days and overtime pay of 25 to 50 percent of a worker's hourly salary for time worked beyond 35 hours. Others who have dared to suggest returning France to the previous official workweek of 39 hours, including former President Nicholas Sarkozy and the current prime minister, Manuel Valls, were promptly shouted down.
Instead, Mr. Macron is pushing for new legislation to let companies negotiate their own wage and work-time agreements with unions internally, rather than relying on sectorwide accords negotiated between employers associations and unions.
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As it is, previous governments have already pushed through a raft of measures to weaken the law, which does not apply to white collar workers or senior executives, but caps the official workweek for government employees and workers like Ms. Ahlem.
Various loopholes have increased the amount of extra hours that employees can work before overtime pay kicks in. And the government pays billions of euros a year in subsidies to help companies offset overtime costs. Analysts question whether the 35-hour week has brought economic benefits — or merely bureaucratic burdens.
Companies were expected to recruit more employees to compensate for the reduced hours for any one worker. While the French statistics agency Insee estimates that 300,000 to 350,000 jobs were created shortly after the law was passed, economists said that the pace of jobs creation had not been maintained. And critics say the rule is a reason that France's unemployment rate is more than double Germany's rate of 5 percent.
Myriam Bello is one of nearly 4.5 million workers in France unable to find jobs with at least 35 hours a week.
"It's not nearly enough, especially when you see that people in other countries work more hours than us," said Ms. Bello, 22, who has a 30-hour-a-week contract at a New Look clothing store just outside Paris. "If you need to rent an apartment, and the agencies ask that you earn three times the monthly rent just to sign a contract, it's impossible."
"To this day," Ms. Bello added, "I cannot find a 35-hour-a-week contract."
Abolishing the law would require a wholesale review of the exemptions and subsidies now in place, said Jean-François Roubaud, the president of the C.P.G.M.E., France's main employers' association for small and medium-size businesses, leading to "major difficulties."
For the moment, his association is resigned to keeping the 35-hour workweek in place — as long as Mr. Macron follows through on his promise to provide employers with more flexibility.
"Only in France," he said, "would you find something this complicated."