Pret A Manger has launched a trial in its three London-based Veggie Pret stores to see if it can reduce the "millions of tonnes [of plastic] ending up in oceans each year".
Veggie Pret in Exmouth Market, on Great Eastern Street and on Broadwick Street are encouraging customers to fill up their bottles for free using new filtered water stations.
They have also started selling two sizes of reusable glass bottles alongside regular water bottles to give people the choice between reusable and disposable. The aim is to understand if customers will choose to refill a bottle rather than buying a new plastic one.
Clive Schlee, CEO of Pret said: "Plastic bottles are a problem. We all feel it even before we hear the shocking statistics about millions of tonnes ending up in our oceans each year and imagine the devastating impact this has on marine wildlife.
"We are making inroads on the problem of packaging waste by reducing where we can and making more of it recyclable. This includes working to find a solution to the fiendish coffee cup problem. We recognise we have lots to do.
"Plastic bottles present a real challenge and there are two schools of thought within Pret. The passionate environmentalists say stop selling them altogether, while the pragmatists say make it as easy as you can for customers to use fewer plastic bottles. We are looking carefully at both options."
This year, Pret saw sales grow 15% to £776.2m, driven by sales in dairy- and gluten-free ranges. Pret introduced a number of dairy-free products in 2016, including a dairy-free, gluten-free soup range all under 250 calories. The new offering increased UK soup sales by 16% like-for-like.
Since the first Pret opened 30 years ago, the brand has been donating unsold food to the homeless every night. This week it was announced that Pret would donate unsold food from two new university stores in London to the Ronald McDonald House charity.
Pret A Manger and Petit Pret opened at St George's, University of London, on Tuesday (17 October).
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