Taylor Swift has made an unexpected stage comeback in London.

The singer appeared as a surprise guest at a concert by the US band Haim on Thursday.

Along with sisters Este, Danielle and Alana Haim, with whom Swift has been close friends for years, she sang a mix of the Haim song "Gasoline" and her own hit "Love Story".

"I haven't been on stage for a very long time," Swift said in front of almost 20,000 enthusiastic fans in the sold-out o2 arena.

"It's nice.

It is very nice!

When I heard that my girls were playing at the o2 in London I thought: I have to see that.

And it looks like about 20,000 other people had the same thought.”

Actually, Taylor Swift was supposed to perform in London's Hyde Park and at the famous Glastonbury Festival in England in 2020.

However, both performances were canceled due to the corona pandemic.

Since then, Swift fans have been waiting for the announcement of a new tour.