The Scottish Fold kitten appears at the end of the advert after Swift buries herself in fluffy cats. The 24-year-old singer announced the ad spot Wednesday on Twitter, ahead of the commercial's television debut Friday.
"Behold, the Diet Coke ad that depicts my perfect world. Featuring a new song and Olivia, who is now a cat actress," she tweeted.
The featured new song is from Swift's upcoming album, 1989. The record is her fifth studio album, and a followup to 2012's Red. The singer has been previewing the album with fans, and debuted lead single "Shake It Off" in August. 1989 is scheduled for release October 27.
Swift recently collaborated with her kitten on a new campaign for Keds. Olivia models next to her owner's "Champion Sneaky Cat" design, which features a a black cat print and "12-13-89" written in gold on the back of the heel. The singer first paired with the brand last year.