Trade unions and left-wing parties have called a day of protest on Saturday - including marches in most big cities - to resist attempts by the centre- right government to relax the laws that enforce the shortest statutory working week in Europe.
The changes - which would allow workers to take more paid overtime and to trade in rest days for cash - would reform, rather than abolish, the 35-hour week imposed by the previous, Socialist-led government.
Both left and right shamelessly exaggerated the scope of the measures in yesterday's preliminary debate, presumably in an attempt to play to the electoral gallery. In the real world, however, attitudes to the 35- hour week cut across the expected boundaries of class and politics.
Recent opinion polls and surveys suggest the shorter week remains immensely popular with white-collar workers in the private sector (who mostly vote to the right). It has always been and remains, unpopular with factory and blue-collar workers, who usually vote to the left.
In strict constituency terms, right and left wing members of parliament lined up on the wrong side of the debate yesterday. The debate, however, has always been more about theory and ideology than reality.
Supporters of the government said the reforms would allow employees to "work more and earn more".
Left-wing politicians said the changes would "strike the death knell" of the shorter working week, which was the centrepiece of the job-creation efforts of the previous government. The 35-hour law, they said, had become part of the "social status quo" in France. Any attempt to reform it would be an act of "social regression" which would be resisted, in parliament and on the streets.
In truth, calls by unions and the most economically liberal-minded politicians for a radical reform or abolition of the 35-hour week have been stoutly resisted by President Jacques Chirac and the Prime Minister, Jean-Pierre Raffarin. The measures introduced yesterday - and likely to be approved by the national assembly next week - invite employers and unions to negotiate more flexible arrangements if both sides wish to do so. Maximum overtime, already lifted by another reform two years ago, would be increased. Rest times "saved up" by employees could be traded in for cash, rather than extra days off.
Complex debate still rages on whether the original 35-hour law, introduced by the government of Lionel Jospin, was succesful. Left-wing politicians and economists say that the law helped to create jobs and broke down many archaic work practices in France.
On the right wing, the 35-hour week is seen as another layer of bureaucratic interference in the market and a signal to young people that leisure is more important than work.
When the law was passed, it was attacked by the far left as a smokescreen and a swindle. Seven years later, the same far-left parties and politicians defend the 35-hour law as a cornerstone of workers' rights.