PARIS — President Sarkozy moved to end France’s tradition of crippling industrial action yesterday, proposing a law to ensure a minimum level of service during public transport strikes.

The proposal is seen as a test of the new center-right president’s ability to push through a raft of reforms. Mr. Sarkozy’s labor minister, Xavier Bertrand, handed over a 10-page document to union leaders giving them until the end of the year to agree the exact terms of the legislation or suffer an “authoritarian application” of the text.

Striking public transport workers have brought the country to a halt frequently in recent decades, losing the economy millions of dollars, ruining the holidays of many British tourists and repeatedly forcing French governments to cave in to union demands.

The bill makes it compulsory for all workers to declare a strike two days in advance and forbids employees from being paid for days spent on strike. Unions expressed fears that the scheme’s ultimate aim was to end their right to strike.

The existence of a minimum service during strikes is seen as crucial before Mr. Sarkozy tackles a reform of state workers’ so-called “special pensions,” which at present allow transport workers and others full pension entitlements even if they retire early.

Segolene Royal, the defeated Socialist presidential candidate, has confessed six weeks after the election that at least two key measures in her manifesto were “not credible” and were foisted upon her by leftist figures in the party.