Millions of Amazon customers will be blocked from shopping on the website next year after it banned the use of Visa credit cards in Britain following a post-Brexit rise in fees.

The online retailer said it would be forced to stop accepting the credit cards from January 19, blaming Visa's "high fees". Customers will still be able to use Visa debit cards and non-Visa credit cards such as Mastercard or American Express.

Credit cards provided by Barclaycard, HSBC and Vanquis use Visa's payment system, with Barclaycard alone having around 10m credit card customers. Amazon also offers its own credit card, which is operated by Mastercard.

Visa, the biggest issuer of debit cards in the UK, said it was "very disappointed" Amazon was threatening to "restrict consumer choice" by banning its cards.

The public row comes after payment firms were able to hike their fees following Britain’s exit from the EU. Rules from Europe introduced in 2015 capped the so-called interchange fees banks charge retailers when shoppers pay by debit or credit card.

Money expert Martin Lewis said that "because Visa is increasing transaction rates now that the EU cap no longer applies post Brexit" this was a "possible negotiating tactic for Amazon to get its fees reduced".

However Amazon insiders insisted the decision was not about any one rule change. A spokesman for Amazon said that "costs should be going down over time with technological advancements, but instead they continue to stay high or even rise".

James Andrews of money.co.uk, a comparison website, said its decision could force consumers to default towards Mastercard, given American Express is still not accepted everywhere.

"Hopefully, Visa and Amazon work out their differences. In the meantime it would be wise to check your cards now – and think about switching to a Mastercard," he said.

Google searches for Mastercard soared after Amazon's announcement.

This is not the first time a company has rowed with Visa over fees. In 2019 US supermarket chain Kroger said it would no longer accept the credit cards at its Smith's Food & Drug chain, before lifting the ban just months later.

Mike Cherry, the chairman of the Federation of Small Businesses, said the spat highlights how small businesses are being let down by banks and payment providers.

“Small businesses are almost always charged more for card terminals than big corporates - so when online giants start throwing down the gauntlet, you know the situation is becoming critical," he said.

"With banks upping cash deposit and withdrawal fees, and our bank branch network disappearing as card fees spiral, a lot of small firms are caught between a rock and a hard place when it comes to payments."

Roughly nine in 10 British shoppers use Amazon, according to research firm Mintel, with around 40pc using its Prime subscription service. Amazon did not disclose how many customers would be affected while Visa would not reveal how many Britons have a Visa credit card.

Sarah Coles, of broker Hargreaves Lansdown, warned customers that they would need to change the card linked to their account if the ban went ahead.

"This is a massive hassle. If you don’t have an alternative credit card, and you can’t use your debit card, you’ll need to rethink your credit provider or find somewhere else to shop," she added.

Ms Coles said customers could use this to help manage their personal finances and swap to using debit cards.

"Amazon’s checkout process is designed to make spending an absolute doddle, so it can take a matter of seconds between deciding to buy something and making the payment. When the money is going on a credit card, it’s easy to build up debts without really thinking about it," she said.