Comcast is opening its gates to Amazon Prime Video, the cable giant's latest integration with a tech rival that has some of the most directly competitive content yet. 

The two companies said Wednesday that Comcast would be rolling out Amazon Prime onto X1, the cable company's high-tech pay-TV service used by nearly two-thirds of its residential cable-TV customers, over the next week. They announced their planned partnership in August. That means X1 subscribers can watch Amazon's shows, movies and channels like they would any other app on their cable system, and Amazon's content will be available and searchable on Comcast X1 like a regular channel or show

The move comes after Comcast, the biggest cable-TV company in the US, has welcomed digital video competitors like Netflix, YouTube and Tubi TV, after years of tension between traditional pay-TV companies and the streaming upstarts enticing viewers to cut the cord. But Amazon is different: Through its Amazon Channels element, the company allows people to subscribe to premium cable channels like HBO and Starz through Amazon rather than a traditional TV provider. 

That means Comcast X1 customers could choose to pay for and watch their HBO from Comcast itself or on Amazon... through Comcast's own system.

"These kinds of strategic relationships are important milestones because it just reinforces our ambition of making every choice available to our customers -- [put everything] on-demand in one place," said Matt Strauss, Comcast's executive vice president of Xfinity Services, in an interview. "I think the relationship with Amazon Prime is exciting because it's just another proof point of that."

It's also an Amazon first: Amazon Prime Video has never expanded onto a traditional TV provider in the US before. 

Amazon wants to "make sure that customers can watch Prime Video on whatever device they might want to," even if it's a cable company's set-top box, said Greg Hart, vice president of Amazon Prime Video. 

X1 users will be able to flip to any video on Amazon seamlessly from the same interface where they pick from selections of live TV or video on demand. The service's voice-command button on its remote will work with Amazon, so customers can simply tell their TV to turn on their favorite show or anything else on Amazon.

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