With the UK still reeling from more than three years of debates about Brexit, even simple packaging can set off hair triggers, with some fearing any expression of national pride.

In this feverish environment a picture of a Co-Op ice cube bag emblazoned with a British flag and the words “made with British water” has sparked a meltdown on Twitter.

“What is British water exactly? Does it fall on the left, live in a thatched cottage and think itself superior to other races of H2O?” one exasperated commenter asked.

“Water flows here, there and everywhere. Water, like fish, knows no borders. The Co-op has been and should be better than this. Stop it,” another added. “What next? British air?” came another wry response.

The supermarket sought to explain the situation by outlining that its labelling policy dictates that it provides the country of origin of the main ingredients in any product, even ice cubes.

“Sorry if our ice cubes have caused a bit of chill on Twitter,” a spokesperson for the brand said. “But our labelling policy means that we always aim to provide the country origin of the main ingredients in any product, and that includes the water in our ice cubes. We hope our customers are cool with that.”