Furious protests have greeted a supermarket chain’s attempt to circumvent trading laws by opening its Angers branch with automated checkouts on a Sunday afternoon.

French labour laws ban employees of large supermarkets from working beyond 1pm on Sundays.

However, Géant Casino de la Roseraie has found a loophole in the system, staying open past the allowed time with just self-checkout stations in operation and security guards contracted from an outside company.

The large chain’s move, described as the first such attempt in French history to open a large shopping store past the allowed time of 1pm, has not been a popular one with many who feel it puts jobs at risk.

Dozens gathered in opposition outside the large Casino supermarket in the northwestern city of Angers on its first Sunday afternoon opening, waving flags, blocking entry and speaking through megaphones.

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France 24 reported it was the first of its kind of opening, though the Casino chain has already been using its automated checkout system to keep its smaller stores open in Lyon, Marseille and Montepellier.

Other supermarkets around France were also trying out self-checkout and extended Sunday trading options.

While Casino’s latest workaround did not technically break any laws, it drew widespread criticism from local officials, trade unions and some Yellow Vest protesters.

Karine Engel, deputy mayor overseeing commerce in Angers, told France 24 she found the chain’s actions to be “fairly dishonest”.

And trade unionists are concerned the move could lead to people being made redundant as the automated system takes over.

In a release announcing their opposition to the opening a local union, La CGT Maine et Loire, said the move meant “in the long run, thousands of jobs are at stake”.

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In a letter, which they posted to the head of the Casino Group, Jean-Charles Naouri, the organisation also said it posed questions about the role of workers in the chain’s future projects.