Taylor Swift Surprises Fans By Performing 'Love Story' And 'Gasoline' With HAIM [Watch]

Taylor Swift made a surprise appearance during HAIM's concert in London. The singer donned a similar outfit as HAIM band members and performed a "Love Story" and "Gasoline" mashup on the stage at "One More Haim."

The pop band members include three sisters - Alana, Danielle and Este Haim. A fan posted a video of the performance Thursday on YouTube. In the clip, the 32-year-old singer can be seen wearing a black outfit and hugging all the band members before leaving the stage after a powerful performance.

The singer also spoke a few words on stage ahead of her performance.

She said that the idea behind the collaboration was for the crowd "to sing the loudest you have sung all night." She added, "Which is a big challenge because you have been singing very loudly—extraordinary work."

"I haven't been on stage in a very long time," Swift continued, ETOnline reported. "It's nice…it's nice, it's very nice [to be back]. When I heard my girls were playing in London at the O2, I thought, 'I'm going to have to see that.' And it looks like there's about 20,000 other people who also thought that."

One of the fans took to Twitter on Thursday to share a closeup of Swift's outfit, which looked similar to the pop band outfit.

Another fan wrote, "I need to share this moment with you all. this was the moment i couldn’t believe life was real. haim and taylor swift, everyone," alongside a video of Swift performing on the stage.

Swift also took to TikTok to share a video of herself getting ready ahead of the performance.

In the video (later shared by a fan on Twitter), the three band members can be seen fixing their black leather pants together in a corner, and then the camera pans to another corner in the room, which shows Swift also wearing a similar outfit.

"I will forever be grateful to haim for putting taylor swift in leather pants," the fan captioned the video.

"Love Story" music track was originally dropped in June 2009 by Swift while the "Gasoline" music track was dropped by HAIM in 2020.