Amazon adds 3 million Prime subscribers

US online giant Amazon says it added three million customers to its Prime subscription service worldwide in the third week of December as it capped a record holiday season.

Prime, which costs $99 a year in the United States, gives members fast shipping options as well as access to its streaming video, music and other services.

Prime is seen as a way to get more customers into the Amazon ecosystem, including its video service that competes with rivals like Netflix and is investing heavily in its own programming.

"Over 200 million more items shipped for free with Prime this holiday, and members doubled their viewing hours of Prime Video compared to last year," Amazon founder and chief executive Jeff Bezos said.

Bezos added that Amazon's "Man in the High Castle" series based on a Philip K. Dick story became the most watched TV season ever on Prime Video.

Amazon has never disclosed how many customers subscribe to Prime. But the research firm Consumer Intelligence Research Partners (CIRP) estimated it had some 47 million subscribers in the US at the end of September, and that these customers spent more at Amazon than non-subscribers.

Amazon said Sunday it plans to produce 16 feature films a year, throwing down the gauntlet to Netflix, according to comments by Bezos to the German daily Die Welt.

Amazon won five Emmys for the TV comedy series "Transparent" this year. The feature films will hit the big screen and be quickly available on Amazon's online service.