A three-week-long pay dispute that has seen six out of seven fuel refineries in France blockaded, leading to shortages across the country, shows no sign of abating after workers defied government orders to return to work.

On Wednesday the government invoked emergency powers first used 12 years ago by then-president Nicolas Sarkozy, to requisition the facilities — meaning compelling a certain number of workers to deliver a minimum service — in an effort to break the deadlock, with those who reject the summons facing fines or even jail time.

The hard-left CGT union said such a move was "not necessary and illegal", calling it the "choice of violence", and saying that it could lead to the union withdrawing "its participation in meetings with the government and business leaders during this period".

Government minister Christophe Bechu accused the unions of unreasonable behavior.

"In one of the two companies the unions have got an agreement with majority support and nothing has changed, and in the other striking is being used to put pressure on dialogue," he said. "These aren't situations that are acceptable for millions of French people."

Economy and Finance Minister Bruno Le Maire added that "many of our compatriots are revolted and I understand them".

"I believe that in the first stage, we must give negotiations a chance, a negotiation needs to be in good faith and cannot drag on, because our compatriots are legitimately fed up, they want a quick solution, we owe them a quick solution."

The Connexion France news website quoted Prime Minister Elisabeth Borne as saying that the government "cannot let the country be blocked".

"It will continue to take measures to facilitate the supply of petrol stations as it has been doing for several days but everyone must take responsibility. The government will take its own," she said.

The Ukraine conflict is affecting fuel prices in France, just like elsewhere in Europe, which makes the huge profits of companies such as TotalEnergies even more infuriating for the unions, who are demanding a 10 percent pay rise for staff.

On Sunday, a protest march against the high cost of living and President Emmanuel Macron's policies, including highly contentious changes to the convoluted French pension system, is due to take place.

Currently most people in France are able to retire at the age of 62, but dating back to before the pandemic, Macron has wanted to bring in changes that would raise the age to 64 or 65, and it is believed that he wants to get the issue resolved once and for all this winter. The ongoing refinery standoff just adds to existing disagreements and division.

"I hope this is the spark that begins a general strike," Green Party member of Parliament Sandrine Rousseau told the Franceinfo radio network.