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Amazon has raised the stakes in its fight with Apple and Google by kicking their video devices out of its online store.

The retail giant sent a letter to its marketplace sellers saying it would stop selling Apple TV boxes and Google’s Chromecast sticks effective Oct. 29. Amazon issued a statement confirming the development, which was first reported by Bloomberg.

“Over the last three years, Prime Video has become an important part of Prime,” a spokesperson said. “It’s important that the streaming media players we sell interact well with Prime Video in order to avoid customer confusion. Roku, Xbox, PlayStation and Fire TV are excellent choices.”

Let’s try to translate that: We’re competing with Apple and Google, so we don’t want to help them by selling their devices.

Amazon already has a strained relationship with Apple over competing media distribution strategies. See, for instance, the Apple antitrust book case, in which Amazon sided with the federal government and against Apple and the major book publishers.

And while you can view Amazon’s streaming video service on iOS apps, you can’t subscribe to the service or buy videos via the app, because Amazon chafes at the 30 percent cut Apple takes for subscriptions sold through its App Store and of in-app purchases.

Then last month, when Apple announced its updated version of the Apple TV at an unveiling event San Francisco, the company touted the availability of a host of high-profile online video subscription services — among them Netflix, HBO, Showtime and Hulu.

Amazon’s Prime video service was the notable omission.

Amazon also has a strained relationship with Google. That’s in part because of Amazon’s decision to use a “forked” version of Android for its tablet software, but it’s mostly because Amazon is increasingly cutting into Google’s core search business. Amazon doesn’t have a video app for Google’s Chromecast or Android video devices, either.

Apple’s new box is supposed to go on the market in late October, the same time that Amazon’s ban kicks in. Amazon, Google and Roku are also rolling out new versions of their streaming hardware. Amazon introduced its first streaming TV box and stick in 2014; Parks Associates reports Amazon overtook Apple for third place that year.

Google and Apple declined to comment.

Additional reporting by Mark Bergen.