Aldi is trialling paper and compostable bags in a bid to remove more than 33 million plastic bags from its estate.

The discounter will divide its 830 stores in half under the pilot next month, with some offering paper bags and the others offering a compostable alternative.

The paper bags are sourced from sustainably managed forests and will be strong enough to carry up to 11kg of groceries. They will cost customers 19p each.

Aldi’s compostable bags will retail at the lower price of 6p.

At the end of the test, the option that proves most popular with customers will be rolled out across the grocer’s UK portfolio.

Aldi said the move could save up to 1,300 tonnes of plastic per year – the equivalent of 33.3 million single-use carrier bags.

The value food operator has also set out two new pledges as part of a broader crackdown on plastic.

Aldi has vowed to axe “difficult to recycle packaging” – such as PVC, polystyrene and non-detectable black plastic – from core grocery ranges by 2020, and plans to slash all plastic packaging by 25% by the end of 2023.

As part of those drives, Aldi will launch two further bags later in the year. One will be made entirely from the grocer’s back-of-store waste, while the other will be a reusable cotton alternative.

Aldi’s managing director of corporate responsibility Fritz Walleczek said: “Reducing the amount of plastic we produce is fundamental to our commitment to being a sustainable and environmentally responsible business. This trial will identify the option which best suits our shoppers.

“Cutting waste is part of Aldi’s DNA and we are constantly looking for new ways to reduce our environmental impact. This new trial is one of the biggest we have ever launched because we want our customers to be involved and help us make the right decision for them and the environment.”