Taylor Swift 'reached out' to Kendrick Lamar for Bad Blood

Taylor Swift "reached out" to Kendrick Lamar for their 'Bad Blood' collaboration and he had no hesitation in saying yes because he's always been a "fan" of her music.

The American rapper appears on the single version of Taylor's latest track and he agreed to add some lyrics to the song after the 23-year-old pop star contacted him personally.

Talking on 'The Ellen DeGeneres Show', Kendrick said: "She reached out. I've always been a fan of hers, and she was a fan of my music and she reached out and we got it done."

The track is the fourth single taken from the 'Shake It Off' hitmaker's '1989' album and the elaborate video, which features models of the moment Karlie Kloss, Gigi Hadid, Lily Aldridge and Cara Delevingne, managed to break Vevo records in the first 24 hours with over 20 million views and shot straight to the top of Billboard Hot 100 chart.

The promo also features cameo appearances from Cindy Crawford, Selena Gomez, Jessica Alba, Ellen Pompeo, Lena Dunham and Mariska Hargitay, while Kendrick also appears in several scenes.

During his appearance on Ellen's show, Kendrick performed 'These Walls' from his current album 'To Pimp A Butterfly'.

The 27-year-old hip hop star was also asked by host Ellen about what it meant to him to be a positive role model for his fans.

He said: "It means everything to me because I know there's a lot of kids in my neighbourhood that are watching TV and saying, 'You know what? I want to be a positive influence just like Kendrick Lamar,' or whoever is out there doing something for the good."