San Francisco, California - A US judge issued a permanent injunction on Monday against Google, siding with competitor Epic Games and ordering the internet giant to change conditions on its app platform Play Store to make it more competitive.

Google plans to appeal the ruling.

Judge James Donato, ruling for the US District Court's Northern District of California, ordered that Google may not require app developers to use the internet company's own payment system in the Play Store, starting from November 1.

Additionally, developers must be allowed to inform users within the Google platform about where their apps can be obtained outside the Play Store.

Google may also not offer developers any incentives for not bringing their apps to competing app stores.

The rules apply only to the US. In the European Union, the Digital Services Act already has its own rules for large online platforms.

Google could lose revenue in its US app business as a result of the decision.

The internet company reiterated earlier criticism that the conditions required by Epic would only benefit the gaming company but could harm users, app developers, and device manufacturers.

Google has criticized the court, saying it considered the Android smartphone business to be a separate market and did not take into account competition from Apple's iPhone.

Rival app stores have been allowed on Android smartphones for a long time. In the Epic trial, however, jurors concluded that Google had used unfair means to make business difficult for them.

After the ruling, Epic chief executive Tim Sweeney announced that the company would launch its own app store within Google's Play Store in the US next year.