The maker of Fortnite has filed a complaint with the UK’s competition watchdog, accusing Apple of anti-competitive behaviour over the way it runs its App Store.

Epic Games has made the complaint in support of an investigation by the Competition and Markets Authority (CMA) against Apple, which was opened earlier this month.

The CMA is looking into concerns that Apple’s terms and conditions for app developers on the App Store are unfair and whether it abuses its dominant market position over the distribution of apps on Apple devices in the UK.

As well as manufacturing the likes of the iPhone and the iPad, Apple controls the App Store, which is the only way for developers to distribute apps on to Apple’s ecosystem and the only way for the public to access them.

It is this control that Epic Games says is unfair, and, in a statement announcing the complaint, said Apple’s “prohibitively restrictive rules governing the distribution of apps and payment processing” broke UK competition law.

Apple has accused Epic of wanting to “operate under a different set of rules” from other developers.

The row between Epic, Apple and another tech giant – Google – began last year when Fortnite was removed from both the Apple App Store and Google’s Play Store after Epic introduced a new payment system for in-app purchases that circumvented Apple and Google’s own app store payment systems.

Epic argued that this system was unfair because the two companies take a commission per transaction made on their respective stores, and no alternative payment systems are allowed to be used.

In response to Fortnite’s removal from the app stores, Epic Games has launched legal action in the US and Australia against both firms and filed an antitrust complaint against Apple in the EU, which is also in support of an ongoing investigation by the European Commission.

The Fortnite maker said it is not seeking monetary damages in any of the cases, but rather is pushing for “regulatory remedies” which will prevent the “intentional distortion and manipulation of the market and ensure fair access and competition for consumers and developers in the UK and around the world”.

Epic Games founder and chief executive Tim Sweeney said: “By kneecapping the competition and exerting its monopoly power over app distribution and payments, Apple strips UK consumers of the right to choose how and where they get their apps, while locking developers into a single marketplace that lets Apple charge any commission rate they choose.

“These harmful practices lead to artificially inflated costs for consumers, and stifle innovation among developers, many of whom are unable to compete in a digital ecosystem that is rigged against them.”

In response to Epic’s complaint to the CMA, Apple said: “It is not surprising that Epic is pushing their agenda before the UK Competition and Markets Authority, as we have seen them use the same playbook around the world.

“Now that they have achieved massive success through the App Store, becoming a multibillion-pound corporation, Epic wants to operate under a different set of rules than the ones that apply to all other developers.

“The result would be weakened privacy and data security protections for our customers, and we think that’s wrong.”