Glastonbury festival organiser Michael Eavis has demanded an apology from rock band The Darkness after singer Justin Hawkins' verbal attack on him.
The Darkness are currently on a sold-out US tour
Hawkins said Mr Eavis did not book them for this year's event because he did not think they would be popular enough.
But Mr Eavis told BBC News Online: "We've had a few bands that when they don't get booked, they get upset - and they always apologise."
Sir Paul McCartney, Oasis and Muse have been confirmed to headline the event.
Tickets for this year's Glastonbury - which takes place from 25-27 June at Worthy Farm in Somerset - go on sale at 2000 BST on Thursday.
Hawkins' spokesman confirmed that Mr Eavis refused to book them around Christmas because he "said he thought we wouldn't be around for the festival in June".
Hawkins said the band then knocked back Mr Eavis' approach to them when he approached them later.
"Michael Eavis is just annoyed that he missed the boat," Hawkins told The Sun.
The Darkness are one of the headline bands at this year's Reading and Leeds festivals in August alongside The White Stripes and Green Day after becoming one of the most talked-about bands in the UK.
On Wednesday, Mr Eavis said he did not book them for this year's Glastonbury because they played at the event in 2003.
"I'm expecting an apology as soon as he feels in a better mood," Mr Eavis told BBC News Online.
The Darkness opened the festival in 2003
And he told BBC Radio Five Live: "I think the ego's gone to his head a little bit - I think he's got a bit of a problem with this sudden rise to fame and to stardom.
"He can't quite handle it, I don't think. But they'll be back, I'm sure. I don't bear any malice at all - I don't mind, I can take it."
He said he and The Darkness should work through their differences, and told the NME the band had been "fantastic" when they played Glastonbury last year.
The band had no further comment on Wednesday, a spokesman told BBC News Online.