Apple Music is coming to Amazon's Alexa-enabled Echo devices, Amazon said Friday, in a rare move to broaden Apple's streaming music ecosystem.

It's an unusual move from Apple to allow a third-party voice assistant such as Alexa to control an Apple service such as Apple Music.

Apple has traditionally kept its services and voice-enabled skills locked into its own hardware and has kept rival services such as Spotify and Amazon's music streaming service at arm's length. For example, while you can beam Spotify music from an iPhone to Apple's HomePod speaker using AirPlay, you can't use Siri voice commands to control Spotify. You can only use Siri to control Apple Music.

Echo devices compete directly with Apple's own HomePod. Google's smart speaker, the Google Home, only streams Apple Music through a Bluetooth connection like any regular wireless speaker — the voice-enabled assistant can't launch the service.

Apple Music will be available on Amazon's voice-activated Echo devices starting the week of Dec. 17, Amazon said.

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