Guinness is recalling cans of its non-alcoholic stout because of contamination fears, just two weeks after they were launched.
The brewer described the recall as "precautionary", but said "microbiological contamination" might mean some products were unsafe.
The company urged anyone with cans of Guinness 0.0 not to drink them.
It said it was working with supermarkets and other shops to remove all of the products from the shelves.
The recall only affects customers in Great Britain, as the product was not yet on sale in Ireland or Northern Ireland. No other Guinness drinks have been recalled.
Guinness 0.0 was launched to much fanfare in supermarkets on 26 October, having taken the brewer four years to perfect.
In a statement, the brand, which is owned by Diageo, apologised to customers.
"We wanted to let you know that as a precautionary measure, we are recalling Guinness 0.0 in Great Britain because of a microbiological contamination which may make some cans of Guinness 0.0 unsafe to consume.
"If you have bought Guinness 0.0 do not consume it. Instead, please return the product to your point of purchase for a full refund.
"Alternatively, contact the Diageo Consumer Careline... with details of your purchase to receive a refund voucher before disposing of the product."
On its website, the brewery also says its team is "working hard to investigate and determine the root cause" of the contamination.
Several concerned social media users called on the firm to issue further information on the type of contamination as soon as possible.
The new stout was created in response to what Guinness said was growing consumer demand for lower-calorie and non-alcoholic drinks.
It is produced with the same amounts of water, barley, hops and yeast as a traditional Guinness, before the alcohol is removed using a cold filtration method.
At the time of launch, Guinness bosses insisted that none of the traditional flavour had been lost, with the seal of approval being given by independent taste testers.
The new product was due to become available on draught in pubs next spring, before being launched in other parts of the world later in 2021.