The government is fighting to overcome union opposition to its plans to reform France's pension system. It wants to push back the age at which retirees would be eligible for full pensions from 62 to 64.
It also wants to end some of the special pension deals that allow a minority of workers to retire in their fifties.
The government insists the new system will be fairer to all French workers and be financially sustainable. The government appealed for compromise before the resumption of talks at the Labor Ministry with unions and employer representatives.
Tuesday marked the 34th day of disruptive train strikes and walkouts in the Paris Metro.
Oil refinery workers joined the walkouts Tuesday. Union leaders vowed that "not a drop" of gasoline would be allowed through strikers' lines, seeking to pile pressure on the government with the specter of possible shortages at pumps for motorists.
Emmanuel Lepine, representing chemical industry employees at the CGT union, said workers were striking at seven of eight French refineries. He said their walkouts would last through Friday.
Workers are demanding "the withdrawal of this reform that no one wants," Lepine said on France Info radio.
The government played down the impact of refinery disruptions, saying France has fuel stocks to last beyond three months and that more than 98% of the country's 11,000 gas stations are completely unaffected.
Prime Minister Edouard Philippe said Tuesday ahead of the talks that the government remains determined to push through the reform. He said it would create "a better retirement system tomorrow than the one that exists today."
He appealed for union flexibility, while indicating that the government is prepared to consider concessions, too.
"To find a compromise, everyone has to budge a little bit," Philippe said on RTL radio.