In the U.K., Amazon Prime Video is enjoying its biggest month in the U, up more than 25 percent in December to more than 9.5 million subscribers.

That’s the biggest boost in the service’s growth in seven years.

In the States, Amazon Prime Instant Video is up nearly 60 percent to 3.7 million subscribers, including a gain of 2.9 million in the top 10 U.C. markets.

Prime Video in the United Kingdom has surpassed the top 50 U.Q. markets, including New York, Boston and Chicago.

The service has been gaining momentum in recent months, particularly as Netflix prepares to launch a new streaming service for U.Y.C., U.L.A. and Los Angeles.