Amazon scored a deal Wednesday to distribute old shows from premium cable TV channel HBO to its monthly Prime subscribers, landing a blow on rival Netflix in the streaming video battle. Amazon said the multi-year deal would allow it to stream top HBO shows from past years like "The Sopranos", "The Wire" and others to Prime Instant Video service customers, who pay a monthly fee for unlimited viewing. Until now HBO had distributed its shows via streaming to customers of its own HBO GO service. The shows could also be watched on a pay-per-view basis via Amazon and other redistributors. For the newest HBO content, viewers will still have to subscrie directly to the company or watch them on HBO cable channels. Amazon Prime customers will get access to popular shows like "Girls", "The Newsroom" and "Veep" around three years after HBO broadcasts them, the companies said. No mention was made in the announcement of HBO's current hit, "Game of Thrones". "HBO original content is some of the most-popular across Amazon Instant Video -- our customers love watching these shows," said Brad Beale, Amazon's director of content acquisition. "Now Prime members can enjoy a collection of great HBO shos on an unlimited basis, at no additional cost to their Prime membership." The companies gave no information on how much Amazon would pay HBO for the deal. The service officially launches for viewers on May 21. "Given our longstanding relationship with Amazon, we couldn't think of a better partner to entrust with this valuable collection," said HBO executive vice president Glenn Whitehead. The deal amounts to a blow to Netflix, the pioneer in large-scale distribution of video on demand. Netflix has regarded HBO as its principal rival and will now face much more substantial competition from an Amazon offering HBO shows. HBO has built a dedicated audience on its original programming, which has garnered award after award over more than two decades. To compete, Netflix began producing its own original shows in addition to a large catalog of recent and old movies, starting with the broadcast last year of the much-acclaimed "House of Cards."