Waitrose is recalling four varieties of chocolate bars because they may contain pieces of plastic, the Food Standards Agency has said.

The Waitrose 1 white chocolate, white chocolate with matcha tea and pistachio, milk chocolate with pistachio, almond and hazelnut and milk chocolate with feuilletine and sea salt are all said to be affected.

Point of sale notices will be displayed in all of its retail stores which sell the four products, with notices explaining why they are being recalled and what to do if they have purchased them.

The FSA advises people to not consume the products, but to instead return them to the store they bought it from for a full refund.

Product details are here in full:

- Waitrose 1 White Chocolate, best before July 2018 (85g)

- Waitrose 1 White Chocolate with Matcha Tea & Pistacho, best before July 2018 (85g)

- Waitrose 1 Milk Chocolate with Pistacho, Almond & Hazelnut, best before July 2018 (85g)

- Waitrose 1 Milk Chocolate with Feuilletine & Sea Salt, best before July 2018 (85g)

The products affected are all Best Before End July 2018.

It is not understood how this has occurred, but no other Waitrose products are known to have been affected.