Kellogg’s is recalling boxes of its new chocolate cornflakes due to concerns they contain “hard lumps” that could cause damage to teeth or be a choking hazard.

The cereal brand has asked people who bought the packs to dispose of them “as a precaution” after the problem was discovered.

Kellanova, the company that makes Kellogg’s cereals in Europe, said the hard lumps “do not break down when eaten with milk”.

“We have become aware of a very low level of small hard lumps forming in our new Kellogg’s Corn Flakes chocolate flavour,” it said in a recall notice. “These hard lumps of food could cause dental harm or be a choking hazard.”

The Food Standard Agency website also warns customers: “This product may contain small hard lumps of food which makes it unsafe to eat … If you have bought the above product do not eat it. Instead, dispose of the product and contact Kellogg’s.”

The product was launched at the start of this year and billed as bringing a “modern twist” to the 102-year-old brand. At the time the company said of the spin-off flavour: “We’re sure it’s something the whole family will enjoy.”

Kellanova said it believed that only a small proportion of boxes could contain the lumps and that there was “minimal risk” to consumers.

A spokesperson for Kellanova said: “Clusters of cereal forming during production can be a normal occurrence and these usually break up when eaten or placed in milk.

“But, when we spotted that hard lumps of cereal were forming in a very small amount of our new Kellogg’s Corn Flakes Chocolate Flavour cereal, we took the decision to recall all product.”

The recall only relates to 450g boxes bought over a four-month period, and shoppers have been urged to throw away packs with best before dates ranging from 6 December 2024 to 28 April 2025.

Kellanova said that other Kellogg’s Corn Flakes varieties it produces were unaffected by the issue and that affected consumers should contact it for a refund.