(Reuters) - A group that represents audio streaming firms including Spotify ( SPOT ) and France's Deezer in Europe has urged the European Commission to reject Apple's ( AAPL ) proposal in a music streaming case.

Digital Music Europe expressed concern in a letter submitted to the European Commission on Tuesday that Apple's ( AAPL ) proposal to comply with the regulator's March order, in which the iPhone-maker was fined 1.84 billion euros ($1.98 billion), does not provide concrete and effective remedies.

"Apple's ( AAPL ) new entitlement for music streaming services is a discriminatory program that forces competitors to opt into a new regime run by Apple ( AAPL )," the letter added.

Apple ( AAPL ) was fined by the EU in March for thwarting competition from music streaming rivals via restrictions on its App Store.

Subsequently, the iPhone-maker announced measures to make it easier for music streaming apps on its App Store in the European Economic Area to inform users of other ways to purchase digital services, as it looks to comply with a European Union mandate.

Under Apple's ( AAPL ) proposal, streaming services can include links to their websites to inform users of payment options outside its App Store and the company would charge a 27% commission on transactions made through a link.

Apple ( AAPL ) said the developers can provide information about purchases available on their website to users through email as well.

The European Commission and the firms represented by Digital Music Europe, including Deezer, Qobuz and SoundCloud, Jamendo and Soundcharts did not immediately respond to requests for comment. Spotify ( SPOT ) declined to comment.

Last month, Apple ( AAPL ) rejected Spotify's ( SPOT ) new version of iOS app with in-app pricing information for users in the European Union, as the streaming firm does not want to be a part of Apple's ( AAPL ) proposal.

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