Ariana Grande has apologised to the actress who plays horror icon Elvira after she accused the singer of ignoring her during a meet-and-greet.

Actress Cassandra Peterson, who's best known for her Mistress of the Dark alter-ego, said Ariana Grande had requested tickets for herself and family members to one of her stage shows.

She told a panel that she'd posed for photos and signed autographs for "all her friends and relatives" but that Ariana had refused to pose for a picture in return and left before the performance.

Responding via Instagram, Ariana Grande said she was "disheartened" to see the comments and claimed she'd left the event early because she "had an anxiety attack".

In her response to Cassandra Peterson's post, Ariana said she didn't "even remember" getting to meet the star.

She said the event would have happened about seven years ago after her concert in Manchester was targeted in a terror attack.

At the time, Ariana said, she "was really not great with being in public crowds or loud places".

"But if I'm misremembering this moment, I sincerely apologise for offending you so.

"Thank you for being so nice to my mum, she told me how lovely you were (she might have different feelings about that now but I'll talk to her... clearly, we all have our days!)."

She signed off by "sending love always", adding "You'll always be our queen of Halloween".

The video of Cassandra Peterson, who also appeared as a guest judge on RuPaul's Drag Race, discussing the interaction, recently went viral.

She's heard laughing when someone else on stage says Ariana is "playing the wrong witch" - referencing her role as Good Witch Glinda in the upcoming film adaption of Wicked.

Fan edits of the movie's poster made using AI have made headlines during a recent promotional tour.

One fan edit turned the image of Ariana and co-star Cynthia Erivo in-character into an animation of the two fighting.

And the stars have also criticised Photoshopped versions of the image, with Cynthia's eyes removed.

"None of this is funny," Cynthia said. "None of it is cute. It degrades me. It degrades us."

Ariana agreed fan edits can go "too far", and that she had "so much respect" for Cynthia and found the issue "very complicated".