LONDON (AP) — Music streaming sites Spotify and Deezer are among European tech companies and trade associations calling on EU officials to toughen proposed legislation aimed at combating unfair business practices by U.S. giants like Apple, Google and Amazon.

In a joint letter, the group urged European Union ministers to go beyond current proposals aimed at regulating online platforms that act as middlemen between customers and businesses.

They said that the "platform-to-business" regulation doesn't go far enough to ensure dominant tech companies avoid practices that "reinforce their privileged position or unfairly favor proprietary services."

Spotify CEO Daniel Ek and Deezer CEO of Hans-Holger Albrecht were among the signatories to the letter, which was sent to ministers on Monday.