Protesters are fighting the government’s plans to reform the nation's pension system by raising the retirement age.
Marseille, the nation's biggest port by tonnage, and Le Havre, the largest container hub, bore the brunt of the walk-out as they were already struggling to recover from a two-day shutdown over the weekend in an unrelated dispute over port labor reform.
The port of Marseille said 85 ships have been affected by Tuesday's strike, including 56 oil and product tankers unable to berth because of a separate stoppage at the nearby Fos-Lavera oil terminal which entered its 16th day Tuesday.
Oil refinery workers also walked off the job across France, aggravating a growing shortage of gasoline supplies caused by the bitter dispute at Fos-Lavera over government plans to privatize stevedoring operations previously run by port authorities.
Even though the majority of dockworkers have accepted privatization at publicly-owned ports, they have staged strikes over the past three weekends to protest the government's alleged failure to deliver on pledges to boost jobs on the waterfront.
Tuesday's strike also hit rail cargo traffic as union leaders at state-owned SNCF threatened to escalate action to include rolling stoppages if the government does not water down plans to raise the retirement age in France to 62 from 60.
Around 30 percent of flights were cancelled at France's biggest airport Paris Charles de Gaulle, mostly domestic and short haul intra-European services, leaving cargo and long haul traffic relatively unscathed.
The strike halted an estimated 50 percent of flights at France's second largest airport, Paris Orly.
Tuesday's strikes and demonstrations are larger than the previous two protests, but President Nicolas Sarkozy is vowing not to water down pension reform, one of his flagship policies.