Waitrose has pulled two batches of frozen beef meatballs from shelves because some of the products might contain pork.

The retailer said batches of its Essential Waitrose 16 British beef meatballs produced last summer may contain pork. It relates to products dated best before June 2013 and best before August 2013.

Waitrose said tests had been done on the product and even though the results had been contradictory, it had taken the precautionary measure of removing the meatballs from sale and putting up customer notices in all branches.

“The meatballs are safe to eat but pork is not listed as an ingredient and should not be part of the recipe,” it said in a statement.