(CNN) Fresh from banning single-use plastic bottles, Britain's Glastonbury Festival has taken another step towards sustainability: sandwiches in 100 percent compostable packaging will be sold at the five-day event.

The sandwiches will be sold at a pop-up store run by the British food retailer Co-op at the festival, which begins Wednesday.

"All components of the packaging for these sandwiches, the base card, the film and the label, are compostable," Co-op said in a statement sent to CNN. Compost waste bins will be available at the festival, Co-op said, while the pop-up store will also offer recyclable aluminum cans of water, refillable water bottles and compostable carrier bags.

Co-op has pledged to no longer sell "hard to recycle" own brand plastic packaging and products by 2023.

The festival has a purpose-built recycling center to process litter from its 135,000 guests.

Breige Donaghy, food director at Co-op, said: "It's a priority to find new ways to reduce plastic packaging. We've successfully unveiled compostable carrier bags but it's difficult to replace plastic packaging for sandwiches and keep the product fresh. These sandwiches have two days shelf life from the moment they are made and we have to deliver directly to the store."

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