Lorde compares being friends with Taylor Swift to having a chronic illness. Regrets it immediately.

Taylor Swift and her famous friends have been called many things. Like a girl squad. Or a really, really exclusive, celebrity cult for only the most ridiculously good looking.

But comparing being friends to Taylor Swift to having an autoimmune disease? That’s definitely one we’ve never heard before.

The comments were made by New Zealand singer-songwriter Lorde—who naturally, regretted the comparison almost as soon as the words left her mouth.

“It’s like having a friend with very specific allergies,” she said of her friendship with the Bad Blood singer in an interview with The Guardian.

"There are certain places you can't go together. Certain things you can't do. There are these different sets of considerations within the friendship.

It's like having a friend with an autoimmune disease."

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People were quick to call out the comparison as "insensitive," especially as one of Taylor Swift's other best friends, Selena Gomez, has spoken openly about her battle with lupus, a chronic inflammatory disease where the immune system attacks your own tissues and organs.

I wonder how @selenagomez feels about this. What an incredibly ignorant analogy to make @lorde. pic.twitter.com/McbWd058DW

— Stephanie Marie (@stefinitely85) June 19, 2017

Others said living with an autoimmune disease was nothing to joke about.

Living with an auto immune disease is no joke. Try living with one that effects BOTH eye tissues. #ItSucks #autoimmune

— Darrel Adams (@fuhdawin) June 20, 2017

As someone with #CPPS Lorde comparing her friendship with T-Swift as "an autoimmune disease" has really pissed me off.

— Michael McDonald (@__mikes) June 19, 2017

I have a chronic autoimmune disease so according to Lorde I know what it feels like to be Taylor Swift ????????????

— Clara (@ClaraLouOBrien) June 20, 2017

The singer, 20, who has been busy promoting her second studio album, quickly apologised for her choice of words.

"I f***** up & that was really insensitive," she tweeted.

"I'm sorry."

didn't mention taylor, but regardless, i fucked up & that was really insensitive. i'm sorry ????

— Lorde (@lorde) June 20, 2017