Marks & Spencer has several dozen Food Hall stores in Paris and its suburbs, much beloved of British residents of the city for supplying homely delicacies like Breakfast tea, crumpets, sandwiches and ready meals.

But post-Brexit supply problems are taking their toll, and since the beginning of January shoppers have reported virtually empty shelves, with some stores closing their door altogether.

The store at Porte Maillot in the 17th arrondissement was on Monday displaying a sign saying it had received no shipments from the UK due to new government directives on trade between France and the UK.

Since the Brexit transition period ended on January 1st businesses transporting goods into EU countries such as France face a raft of new regulations, especially around animal products.

Any product such as meat, dairy or eggs that derives from animals needs a veterinary certificate stating that it conforms to EU regulations, in addition to the extra customs documentation that all imports into the EU now require.

The strict food regulations apply to both businesses and individuals, so people travelling from the UK to France can no longer bring along a ham sandwich for the journey.

News of the shortages was met with dismay by M&S's loyal customers in Paris.

Marks & Spencer said it was working to solve the problem and hope to have all their lines back on the shelves shortly.

But by Friday there was still no sign of the shortages ending.

M&S stores in Ireland were also reporting similar shortages.

An M&S spokesman said in a statement: “As we are transitioning to the new processes, it is taking a little longer for some of our products to reach stores.

“But we are working with our partners, suppliers and relevant government agencies and local authorities to quickly improve this.”

M&S chairman Archie Norman had warned as far back as August 2018 of this particular Brexit risk.

“If our lorries are sitting in a lorry park near Dover for half a day, that would be the demise of the great M&S sandwich in Paris,” he told The Financial Times.

The sandwiches and other meals for the retailer's 21 food stores in the country – all but one in Paris and one in the northern city of Lille – are made in a factory in central England.

Norman suggested that setting up production in France was not a viable proposition.