Pret A Manger customers will save 25p off every hot drink they buy if they do not use paper cups, it has been revealed.

The sandwich chain is to offer the discounted rate to people who opt to bring in their own reusable cups.

Pret's decision comes months after researchers suggested levying a charge on disposable coffee cups.

Academics estimate that some 2.5 billion disposable coffee cups are used in the UK every year - resulting in about 25,000 tonnes of waste created.

Researchers argued that a study showed that charging might cut the use of disposable cups by up to 300 million a year.