Coca-Cola has signed country music star Taylor Swift to promote Diet Coke, per sources close to the situation.

The move comes on the heels of Pepsi penning a $50 million deal with Beyoncé Knowles six weeks ago and largely underscores an ongoing battle for the youth/music market between the soda industry's two titans. For instance, Coke recently invested $10 million in the digital music service Spotify.

In terms of the Diet Coke-Taylor Swift deal, the singer-songwriter will not appear in the brand's Super Bowl campaign, the sources said. Swift has also served as a brand spokesperson for Cover Girl in recent years.

Meanwhile, a media rep for the Atlanta-based Coke declined to comment.

AdAge first reported the development.