A Katy Perry-Taylor Swift collaboration could happen ... under one condition

Band-aids don’t fix bullet holes, but apologies might.

Katy Perry is willing to end the bad blood between her and fellow megastar Taylor Swift, that is, under one condition: The pop vixen said she would collaborate with T.S. only if she apologizes.

The “Roar” singer’s apparent change of heart came Saturday when a fan tweeted her asking if she’d work with her fellow pop star.

“If she says sorry, sure!” Perry responded.

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For those not riding in either songstress’ squads, Swift famously bad-mouthed a “straight-up enemy” in the 2014 hit “Bad Blood” and extolled on the feud that led up to it in a Rolling Stone profile published before Swift’s 1989 album release — fakeness, tour-meddling and dancer-stealing were alleged. Though Swift never actually named Perry as the purported perpetrator, Perry all but confirmed it was her with a tweet.

“Watch out for the Regina George in sheep’s clothing,” Perry wrote, referencing the the antagonist in the catty flick “Mean Girls.”

“Bad Blood” and its accompanying star-rich fanfare fanned the flames and backed up Swift. Perry watched the events unfold and provided some commentary in interviews over social media.

In a Billboard interview in 2015, the “Roar” singer said that “if somebody is trying to defame my character, you’re going to hear about it.”

Meanwhile, crossover darling Swift has found herself on the receiving end of a few firing squads this summer, publicly feuding with ex Calvin Harris over their breakup and his track “This Is What You Came For” and with Kim Kardashian and Kanye West over the lyrics in West’s “Famous.”

Though Harris called his ex an “amazing lyric writer,” he tweeted that the way their breakup news was leaked was “hurtful” and compared the move to Swift trying to “bury [him] like Katy.”

Soon after, Perry fired off this .gif, which appeared to be her response to Harris’ words.

As for Kardashian and the #KimExposedTaylorParty, the reality star came to the defense of her rapper husband by posting video proof to Snapchat showing Swift coalescing to West’s request that he use the lyrics “I feel like me and Taylor might still have sex / Why? I made that bitch famous” in his song. Swift vehemently denied that she gave her full approval in a lengthy Instagram post.

“Being falsely painted as a liar when I was never given the full story or played any part of the song is character assassination. I would very much like to be excluded from this narrative, one that I have never asked to be a part of, since 2009,” she wrote.

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