The settlement agreed in July was designed to end a seven-year legal dispute over interchange fees, with retailers securing a multi-billion dollar cash payment and significant reforms of Visa and MasterCard rules and business practices.

However, the National Retail Federation (NRF) and big hitters including Walmart and Target have voiced their opposition, claiming that if the case went to trial a judgement could be worth hundreds of billions of dollars.

Judge John Gleeson of the US District Court for the Eastern District of New York has now rejected the concerns and granted the settlement preliminary approval.

Visa and MasterCard have both welcomed the news. Noah Hanft, general counsel, MasterCard, says: "While we recognise some merchants may have different opinions, the settlement represents a solution reached after years of litigation and months of negotiation."

Retail groups have signalled their intention to continue their fight though. Hank Armour, president and CEO, National Association of Convenience Stores, says: "We remain convinced that this is a bad deal and we will look at our options to appeal this decision. This bad deal should not be forced upon the vast majority of merchants and - their customers - who do not want it."