(Reuters) - Video service Netflix Inc unveiled a new feature on Wednesday that allows subscribers to let their Facebook Inc friends know what television shows and movies they are watching and also see friends' viewing activity.

The feature will be available by the end of the week, Netflix said.

Netflix, which claimed to have with 27.2 million U.S. subscribers at the end of last year, said customers will have an option in their Netflix settings to connect to Facebook. If they agree to share information, rows of friends' movie and TV titles will appear in their account.

Netflix said the social features will be tested regularly and could change over time. Social features have been available to Netflix's international customers, but only became an option after Congress "updated a video sharing law earlier this year."

Netflix shares rose 4.5 percent to $190.29 in early trading.

(Reporting By Liana B. Baker)