Asda, Morrisons and The Co-operative have been forced to pull over 30 batches of cheese after alarm bells were raised that they might contain small pieces of metal.

The withdrawal is a major blow for the retailers in their busy Christmas period as it affects a total of 31 batches of cheese across the three retailers.

“Asda, the Co-operative and Morrisons have withdrawn the above products from all of their stores, because small pieces of metal may be present in the products,” the FSA said in an alert issued last night.

Morrisons would not identify the supplier or reveal how many products it had withdrawn. However. it said in a statement: “Only certain use by dates were affected and we have had no complaints.” Asda and The Co-operative did not immediately respond with comment. Notices were being displayed in stores, the FSA said.

The lines being withdrawn are: Asda Smart price mild white Cheddar 385g; Asda Smart Price Red Leicester 385g (six date codes affected across each line); The Co-operative British mild white Cheddar 250g; The Co-operative value Red Leicester (one date code affected across each line); Morrisons M Savers mild white Cheddar 350g (five date codes affected); Morrisons M Savers mild white Cheddar 700g (three date codes affected); Morrisons M Savers grated mild white Cheddar 500g (four date codes affcted); and Morrisons M Savers 10 mild white Cheddar cheese slices 240g (five date codes affected).