Prime Minister Manuel Valls said on Sunday France had enough fuel reserves to tackle shortages at hundreds of gas stations caused by workers blocking oil refineries and depots in protest at an unpopular labour reform.

About 820 stations out of a total of 11,500 petrol stations in France were out of all fuel on Sunday and another 800 were lacking at least one type of fuel, Transport Minister Alain Vidalies told Europe 1 radio.

France has been hit by strikes after President Francois Hollande's Socialist government forced labour reforms through the lower house of parliament on May 10 without a vote. Unions consider the bill unfavourable to workers and want it withdrawn.

"We have the situation fully under control. I think that some of the refineries and depots that were blocked are unblocked or will be in the coming hours and days," Prime Minister Valls told reporters during a visit in Israel.

"In any case, we have the reserves to deal with these blockades."

A prolonged strike at refineries in France in 2010 led to a glut of crude in Europe because it could not be delivered to refineries, a spike in refined products prices due to low output from refineries and shortages at thousands of gas stations.

Protesters have blocked deliveries to gas stations from at least half of France's eight refineries. On Friday workers at three Total refineries voted to halt output by Tuesday. Workers also blocked many fuel depots.

The news of fuel shortages and blockades sent drivers rushing to petrol stations to fill their tanks as a precaution.

Several departments imposed fuel restrictions per vehicle and some banned filling up extra fuel in jerry cans.

"If the situation does not improve and if the government remains deaf to French people's claims, we are heading towards fuel shortage and a significant worsening of our economy," Franck Manchon, coordinator for the union Force Ouvriere (FO) at Total, told Reuters.