French President Nicolas Sarkozy has vowed to maintain his controversial economic reforms despite a second week of crippling industrial action.
He said the reforms were overdue and that they were necessary "to confront the challenges set by the world".
Hundreds of thousands of civil servants joined striking transport and energy workers on Tuesday over the proposals.
The 24-hour action is said to be the largest protest against Mr Sarkozy's reforms since he took power in May.
In his first comments since the stoppage began, Mr Sarkozy said: "These reforms have been put off for too long.
"After so much hesitation, so much procrastination, so many U-turns, a complete break is now needed to stop the decline."
Adopting a defiant stance, he said French voters gave him a mandate to carry out economic reforms when they elected him.
"This clean break I promised to the French during the election campaign. The French approved it," the president said in a speech to an assembly of mayors.
"We will not surrender and we will not retreat," Mr Sarkozy added.
Analysts say Mr Sarkozy is attempting to succeed where his predecessor Jacques Chirac failed, by standing firm against the strikers and completing his reforms.
Opinion polls suggest voters back the French leader's plans to reform "special" pensions which allow transport and utility workers to retire early, but that civil servants have the sympathy of a majority of people.
Teachers, postal workers, air traffic controllers and hospital staff launched a 24-hour stoppage on Tuesday over planned job cuts and higher wage demands, as students continued to demonstrate over university funding plans.
Teachers, civil servants oppose job cuts and want more pay
Newspaper distributors angry at planned restructuring
Transport workers on strike for a week over pension reforms
Students protest at changes they say could exclude poor
Many thousands joined street protests in Paris, Rouen, Strasbourg, Marseille, Grenoble, Lyon and other cities.
The latest nationwide stoppage left many schools closed, hospitals providing a reduced service and newsagents without newspapers.
The French capital's two airports and Marseille airport in the south suffered delays and cancellations.
Finance Minister Christine Lagarde said the dispute was costing France up to 400m euros (£290m) a day.
The CGT union representing French energy workers, who began a 24-hour strike on Monday night, said they had cut nearly 9% of capacity at nuclear plants.
Some are upset over plans to grant universities more autonomy
Rail and bus workers are on their seventh day of an indefinite stoppage against planned pension cuts.
Half of the country's high-speed TGV trains were operating on Tuesday, while in Paris only one metro train in three was in service and less than half of buses were running.
State rail operator SNCF, which is due to hold talks with transport unions on Wednesday, says the number of its workers on strike had fallen since last week.
But with traffic gridlock on Tuesday, the stoppage still caused havoc for millions of commuters across France.
Talks to restart
Eight unions representing 5.2 million state employees - around a quarter of the entire workforce - say their spending power has fallen 6% since 2000, though the government disputes that figure.
They also oppose plans to cut 23,000 jobs in 2008, half in education.
Students are continuing to disrupt classes in half of the country's 85 universities.
'SPECIAL' PENSIONS SYSTEM
Benefits 1.6m workers, including 1.1m retirees
Applies in 16 sectors, of which rail and utilities employees make up 360,000 people
Account for 6% of total state pension payments
Shortfall costs state 5bn euros (£3.5bn; $6.9bn) a year
Some workers can retire on full pensions aged 50
Awarded to Paris Opera House workers in 1698 by Louis XIV
They have been protesting since the start of November over plans to let faculties pursue non-government funding.
The transport workers' strike was triggered by plans to scrap "special" pensions privileges enjoyed by half a million staff.
Transport unions voted on Monday to extend their walkout, but have agreed to attend talks with SNCF on Wednesday.
The government has relaxed its earlier stance that it would not enter talks unless strikers return to work.
On Monday Prime Minister Francois Fillon said rail traffic must "progressively restart" for talks to take place.
But he insisted the government would not budge on its commitment to overhaul the French economy, saying it had a mandate to reform.
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