Pop singer Katy Perry is fighting back against Taylor Swift's hit 'Bad Blood' by releasing '1984', a song that is reportedly a direct response to the former.

Though Swift did not name-drop who she was referring to in 'Bad Blood,' many sources have pointed out that Perry is the subject of single, which describes a feud between people who used to be friends.

A source reported that the 30-year old 'California Girls' singer plans to take down Swift and her posse of supermodel and musician friends with big-named celebrities who are already set to join her group.

The two singers however used to be friends back in 2009, even happily posing together during the MTV Video Music Awards that year. Perry also interacted with Swift a lot on social media, sending her tweets about her cats and guesting during one of Swift's shows.

Apparently, the gap between the two pop stars began and turned out more serious after T.Swiz revealed in an interview with Rolling Stone that 'Bad Blood' was referring to a star rival, who tried to 'sabotage' her whole Arena tour.

Perry responded by saying that, "If somebody is trying to defame my character, you're going to hear about it,".

Prior to writing the '1984' song, Perry had already aired her side and posted a few comments against Swift on Twitter. She tweeted, "Watch out for the Regina George in sheep's clothing..."

Not too long after her controversial post, the brunette beauty later confirmed that she was calling out the 'Blank Space' star with her Mean Girls-themed tweet. 

A source revealed that "Katy was working on some other songs against Taylor, but '1984' will be the main rebuttal to 'Bad Blood'.

The insider added that only people who are familiar with their feud would understand the hidden messages that stirs in the music video. "Apparently the jabs are very subtle but will definitely sting!"

Fans from both sides of this war are definitely on the lookout to when Katy Perry's 1984 music video will drop, and how Taylor Swift will react to it.