Across the English Channel, millions struggled to get to work as a strike by London Underground workers closed much of the city's subway system. It was the first of several such 24-hour strikes planned for this fall.
The strikes came as European Union finance ministers met in Brussels amid worries that the government debt crises that alarmed markets worldwide earlier this year could flare up again. The ministers are discussing introducing a levy on banks and whether a tax on financial transactions can deal with another banking crisis.
In France, the strike coincides with the start of debate in parliament over a plan to overhaul the money-losing pension system so it will break even in 2018. The government insists the reform is essential as people are living longer, and it has urged everyone to show "courage" as it tries to chip away at the huge national debt.
The French retirement age of 60 is already among the lowest in Europe. In contrast, neighboring Germany has decided to bump up the retirement age from 65 to 67 and the U.S. Social Security system is gradually raising the retirement age to 67 as well.
Unions were hoping to mobilize 2 million street protesters at more than 200 demonstrations throughout France on Tuesday, at a time when Sarkozy's approval ratings hover in the mid-30 percent range. A similar effort June 24 drew nearly 800,000 people.
Civil aviation authorities asked airlines to cancel a quarter of their flights at Paris' airports. Only two out of every five of France's famed high-speed trains are scheduled to run during the strike, which began Monday evening and ends Tuesday night.
"If the government wants the next step to go well, it has to give a serious response to the proposals that we ourselves have made," said Francois Chereque, who heads the moderate CFDT union.
Chereque told the RTL station he wants Tuesday's protests to "restore hope" for citizens while putting pressure on the parliamentary debate.
Labor Minister Eric Woerth has said the government will press ahead with the retirement reforms no matter how strong the protest turnout is. Leftist political parties, a leading human rights group as well as student associations have urged members to join in.
The French SNCF rail network said that 80 percent of Thalys trains to Belgium and the Netherlands will not be affected, and Eurostar trains to Britain are expected to run normally.
Post offices were also hit by strikes, as well as newspapers and some radio stations.
French teachers joined in to protest the government's education policies. The Education Ministry said 30 percent of primary school teachers were staying home Tuesday. Some teachers walked off the job Monday.
The thousands of London maintenance workers, drivers and station staff who walked out say job cuts will hurt service and safety.