France's oil industry federation on Wednesday said the country has started using its strategic oil reserves for the first time since 2010.
The move is to counter fuel shortages caused by union-led refinery blockades.
Unions are protesting outside refineries around the country against labour law reforms they claim will hurt workers, threaten labour rights and jeopardise job security.
The government says the reforms will fight high unemployment rates.
Unemployment currently stands at 10%.
The head of Union Francaise des Industries Petrolieres (UFIP) said that a fifth of petrol pumps have already run dry.
The blockades have led to fuel shortages in large parts of France including Paris over the past week.
However, officials say strategic oil reserves are sufficient to maintain regular consumption.
UFIP President Francis Duseux told media that the industry had been using the strategic reserves for two days, while a spokesperson confirmed that "a small quantity" had been used.
Duseaux said, "Every day we use the equivalent of about one day of consumption. At worst, if the situation remains very tense, we can do this for three months."
Philippe Martinez, chief of France’s biggest trade union CGT, said they will continue striking.
In a bid to increase pressure on the government, CGT workers will hold a 24-hour strike at the Nogent-sur-Seine nuclear plant on the southeast of Paris.
The strike will commence at 19:00 GMT on Wednesday.
A spokesman for the CGT’s energy federation said workers at the other nuclear plants will meet to decide on further strikes.
Strategic oil refineries were last used when unions blocked refineries for several weeks in protest against pension reforms in 2010.