Law360, London (January 29, 2019, 6:57 PM GMT) — Vodafone Ltd. sued Visa and MasterCard in London’s High Court on Monday, in the latest action accusing the credit card giants of imposing excessive interchange fees that violate competition law.

In the claims, Vodafone and its affiliates allege that the merchant service charges they’re required to pay for each Visa and MasterCard credit and debit card transaction have been “material times higher” than they should be.

The suit seeks unspecified damages over claims Visa and MasterCard violated both European Union and U.K. competition law.

Vodafone also seeks a declaration that the multilateral interchange fee arrangements dictated by Visa and MasterCard “are and have at all material times been void and unenforceable as being contrary” to the competition laws.

“Visa and MasterCard have forced merchants to pay excessive fees when they accept debit and credit cards. Given Visa and MasterCard’s treatment of merchants, we will continue to bring recovery actions for the losses that our clients have suffered,” David Scott of Scott + Scott LLP, the firm representing Vodafone, told Law360.

Representatives for Visa and MasterCard were not immediately available for comment Tuesday on the litigation brought by Vodafone.

Multilateral interchange fees, or MIFs, are paid by a merchant’s bank to a card-issuing bank when a purchase is processed. They have been at the heart of a spate of antitrust damages claims brought by retailers against MasterCard and Visa.

Claimants are currently waiting for the U.K. Supreme Court to hand down judgment in an appeal brought by MasterCard after it lost a interchange fee case brought by Sainsbury’s Supermarkets Ltd. and several other retails.

The case before the Supreme Court involves five separate cases brought by retailers, including J Sainsbury PLC, Wm Morrison Supermarkets, Walmart Inc. subsidiary Asda Stores Ltd. and Argos Ltd., against both MasterCard and Visa.

Visa had been seeking to uphold a 2017 High Court decision that the transactions were lawful. The retailers meanwhile wanted the appeals court to side with the Competition Appeal Tribunal, which found MasterCard’s actions in breach of competition law and awarded Sainsbury’s damages of around £69 million ($91 million) in 2016.

MasterCard appealed to the Supreme Court, Britain’s highest court, after the Court of Appeal sided with the retailers.

On Monday, a London court agreed to stay a claim brought against MasterCard over interchange fees by a well-known U.K. home entertainment chain, Richer Sounds PLC, in light of the pending Supreme Court ruling.

Vodafone is represented by David Scott, Sylvia Sokol, Belinda Hollway, David Howe and Cian Mansfield of Scott + Scott LLP.

Counsel information for Visa and MasterCard was not immediately available Tuesday.

The cases are Vodafone Ltd. and others v. MasterCard Inc. and others, case number CP-2019-000001, and Vodafone Ltd. and others v. Visa Europe Ltd. and others, case number CP-2019-000002, in the Business and Property Courts, High Court of Justice of England and Wales.

–Additional reporting by Paige Long and Richard Crump. Editing by Alyssa M