However, public transport still remained severely disrupted despite improvements to the service.
The SNCF said support for the strike had dwindled in the past few days.
Nationwide rail services and Paris local transport lines have been running at reduced capacity as workers in local committees met to decide whether to prolong their strike over plans to cut special pension benefits.
Two rail unions called for a return to work, meaning four out of the eight unions were no longer on strike.
The General Labour Confederation (CGT), France's biggest rail union, has refused to issue any instructions to members.
But Didier Le Reste, one of its leaders, said that "the first points have been scored ... There has been a certain amount of progress".
Jean-Daniel Bigarne, leader of UNSA, told members of his union: "We are not calling yet for a suspension of the strike, but we expect a clear move back to work Thursday."
Talks between rail unions and SNCF management are expected to continue for at least a month.
The only union that has refused to take part is Sud Rail.
Nicolas Sarkozy, France's president, has vowed to stand firm over the central point of the dispute, scrapping a privilege that allowed some public-transport workers to retire on a full pension after paying contributions for 37.5 years.
SNCF management has put a $133 million a year financial package of inducements on the table to soften the impact of the changes to the pension system.
|Students and civil servants have also |
taken to the streets in recent weeks [AFP]
Tensions were heightened on Wednesday after saboteurs set fire to cabling on TGV lines in what appeared to be a co-ordinated series of attacks.
Sarkozy called for the perpetrators to be punished "with extreme severity".
A recent poll showed that the president has the support of the public, with 68 per cent believing the strike is "not justified" and 69 per cent hoping that the government "does not give way to the unions' claims".
The strike is costing France around $590 million a day, according to government figures.
Laurence Parisot, the head of the employers' federation MEDEF, said it was a "disaster".
The strike, which began on 13th November, has been seen as a key test of the credibility of Sarkozy who was elected in May on a platform of economic reform.
The protests reached a peak on Tuesday when civil servants also staged a one-day strike over pay and job cuts and some civil service unions warned they might renew their protests next month.
Students in some universities and high schools have kept up their own demonstrations over education reforms and plan to hold rallies in several cities.