Workers at petrol refineries across France joined the pension reforms strike this week, sparking fears of shortages at fuel stations across the country.
It was part of a nationwide walkout over the government's proposals, which include raising the minimum retirement age from 62 to 64.
The CGT union claimed every refinery in the country was affected and little to no fuel was being distributed to petrol stations on Tuesday.
"France's eight refining sites are 'all blocked'", reported FRANCE 24's Science Editor Shirli Sitbon.
Despite continuous production, protesters have shut the gates to refining sites and "will not let the fuel leave", she said.
Meanwhile three out of France's four liquefied natural gas terminals are blocked while output from the country's nuclear plants has also been cut.
Warning of potential shortages if the strikes were to continue, Sitbon nevertheless said the impact may "not be as drastic" as it was during former strikes as more people are working from home.
There is no lack of fuel in our service stations
TotalEnergies — which operates three of the country's six refineries — said although oil product movements out of its facilities have been blocked, "there is no lack of fuel in our service stations".
The company said stocks at depots are high. "Our teams are ready to meet demand which could be higher than normal, with additional logistics resources, if needed," it said.