Tesco Go: The UK supermarket chain is trialling an Amazon-style version of checkout-free shopping

Tesco has said it is testing a way of paying for your shopping in-store without going through a checkout, using a smartphone app to scan items and pay online.

The app is being tested in a Tesco Express near its headquarters in Welwyn Garden City, which is also one of the retail chain's cashless stores.

“Using your mobile device you select some products, put them into your basket on your device and then just walk out of the store,” Steven Blair, Tesco’s convenience transformation director announced to press yesterday.

“The feedback is very good on it but it’s super early,” he added.

Amazon began trials for a similar scheme in a purpose-built store in Seattle earlier this year.

Read more: Amazon officially opens its check-out free supermarket to the public

Known as Amazon Go, the Seattle store uses cameras and sensors to track customer activity, and check what they take off shelves and put back. Customers are then billed via their Amazon account once they leave the store.

Tesco's chief executive Dave Lewis told Reuters that although the Welwyn trial had scalable potential, security implications had to be considered as there was a danger of increased product theft.

"If the margin in the business is 2 or 3 per cent, you don't have to lose much to make it unprofitable," he said.