German gummy bears, chocolate and liquorice are popular sweets in Britain, but aficionados there might have to start stockpiling before the country leaves the European Union.

German sweet retailers are worried that exporting products to the United Kingdom will become as slow as molasses after Brexit day on March 29, with new, unclear customs regulations potentially causing supply shortages and price increases.

“We don’t even know which customs form to fill out and which customs class we’ll be in,” Bastian Fassin from the Association of the German Confectionery Industry told the German news agency dpa.

Germany delivers 800 million euros (919 million dollars) worth of sweets to Britain each year and up to 3,000 jobs in Germany are linked to these exports, making Britain the second biggest importing country of German sweets after France, according to the dpa news agency.

Germany Candy Fair Brexit
Lollipops handmade in the EU (Martin Meissner/AP)

If Britain leaves the EU, it can no longer take advantage of free trade with the other 27 European nations that are part of the bloc.

Beyond shortages and supply delays, the German sweets may become more expensive once they have finally cleared customs and arrived in Great Britain, said Olaf Wilcke, the sales director of Sperlari, who was attending the ISM fair in Cologne, one of the world’s biggest trade fairs for sweets and snacks.

Germany Candy Fair Brexit
British sweetmaker Mr Stanley shows his sweets boxed in a black cab at the international candy fair (Martin Meissner/AP)

If this leads to a drop in consumption, the fear is it will lead to job losses in the German industry.

“That’s not good,” Mr Wilcke said.

“We have free borders in Europe. That’s what we wanted.”

The market insecurities work both ways, meaning British sweets producers exporting to Germany will likely also be affected.

Germany Candy Fair Brexit
A display dummy wears golden German lebkuchen (gingerbread) (Martin Meissner/AP)

More than anything, producers and retailers from both sides of the English Channel at the sweets trade fair in Cologne were hoping for better information, quickly, on how future trade between Britain and the EU will work.

“What we’re waiting for is clarity on the Brexit deal,” said Sandra Sullivan, the director of the British Food and Drink Association.

“That’s something that companies need with such a short space of time between now and the end of March.

“It’s really important that the government pushes forward and gives up the information we need to be able to plan for the future,” Ms Sullivan said.