Be warned, Kanye: Taylor Swift has written a song about you, and she’s singing it at Sunday’s MTV Video Music Awards.

The country superstar’s win for best female video last year was marred when Kanye West got on stage and said it should have gone to Beyonce.

Swift wrote a song about the experience earlier this year, and a source familiar with the show said Saturday the 20-year-old will sing the new song at the VMAs, which will be aired live on MTV. The source did not want to be identified because of the sensitivity of the matter.

The song is on Swift’s upcoming album “Speak Now,” due out in October.  The source said Swift performed it during a secret rehearsal in Los Angeles for the VMAs on Friday.