The launch of Amazon Dash service could take away 20% of UK supermarket online sales by 2020, according to e-commerce delivery expert ParcelHero.

David Jinks, head of consumer research at ParcelHero, said: “Dash is an ultra-convenient device. With the simple push of a button – or even by speaking to the gizmo for some versions – it will reorder your washing powder or your coffee or one of 40 products at launch.

“It’s great news for busy people as it takes care of routine shopping chores automatically; but it’s very bad news for supermarkets as it ties consumers into Amazon for even more products.

“If Amazon can take a 20% slice of that online grocery market pie it’s going to leave at least one lower-margin supermarket chain struggling longer term, as shoppers desert the high street.”

Amazon has spent millions in the last three years developing its delivery service in the UK. The company dominates the UK e-commerce market with sales of £4.4bn, and could be set to make inroads into the supermarkets’ online profits.

However, other industry experts have disagreed with ParcelHero’s prediction, arguing instead that Amazon will only take 3% of the grocery market.

In June, Ocado shares hit a three-year low following the UK launch of Amazon Fresh.