The singer, who is believed to be marrying Sam Cooper in a private ceremony on June 11, has allegedly been offered a backstage VIP area to allow her to celebrate her nuptials at the three-day music event in Somerset next month.
Festival organiser Michael Eavis told The Sun: "Lily's coming down for her honeymoon. We'll look after her - she'll get well treated. I've known her since she was tiny. She's such a star. I'd love to get her out of retirement. I'm really looking forward to her wonderful wedding."
Earlier this week, Allen took to her Twitter page to rant about her "nightmare" wedding plans, saying: "Tip of the day: don't ever get married. Everyone involved (or not, as the case may be) turns into a c**t. Is there a train station for Gretna Green?"
The singer previously used the microblogging website to express her anger at the "d**k" who leaked her 'save the date' card. She wrote: "You're not invited anymore. Have some respect and stay at home."
U2, Coldplay and Beyoncé have been confirmed as headline acts at this year's Glastonbury Festival.
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