French students and unions have vowed to keep up the pressure on the government with further action over the new law on youth employment contracts.
Protests started last week and resulted in clashes with police
Riot police were used to evict 200 protesting students from Sorbonne University in Paris at the weekend.
Student unions are now planning street demonstrations against the law on Tuesday, Thursday and Saturday.
The French prime minister has defended the law, saying it will help less qualified youngsters find work.
Speaking on French television, Dominique de Villepin said the First Employment Contract (CPE), passed by parliament on Thursday, would especially help those in the suburbs - where the youth unemployment rate is up to 40%.
It is a contract for under-26-year-olds which employers can break off at any time within the first two years, without explanation.
Ministers hope the flexibility will encourage employers to hire more young people, safe in the knowledge that they will be able to get rid of them - unlike most French contracts, which employers say make them wary of taking on new staff.
The BBC's Caroline Wyatt says the furore leaves Mr de Villepin in a tricky position - as a protege of President Jacques Chirac, he is likely to hold onto his job, but his chances of running for the French presidency next year will be damaged as his popularity slides.
'The street will speak'
Bruno Julliard, of the UNEF student union, believes protest action will make the prime minister change his mind over the law, which comes into force in April.
"He said that the law will be applied. My reply is that the street will speak," he told the AFP news agency.
"The prime minister has been weakened, and if we push a bit more he will give way."
Students launched protests in dozens of universities last week, culminating in the three-day sit-in at Paris's Sorbonne.
It ended when police stormed in early on Saturday with batons and tear gas, clearing the main building in less than 10 minutes.